From 6aa388b4a386f9d661ec46241a99305d048d52fb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski?= <aundumla@gmail.com>
Date: Wed, 7 Aug 2024 23:39:55 +0200
Subject: [PATCH 01/23] merkle tree draft

---
 src/lib.cairo         |  1 +
 src/merkle_tree.cairo | 17 +++++++++++++++++
 src/utils.cairo       | 26 ++++++++++++++++++++++++--
 src/validation.cairo  | 16 +++-------------
 4 files changed, 45 insertions(+), 15 deletions(-)
 create mode 100644 src/merkle_tree.cairo

diff --git a/src/lib.cairo b/src/lib.cairo
index 7778f44f..962ed1da 100644
--- a/src/lib.cairo
+++ b/src/lib.cairo
@@ -2,3 +2,4 @@ mod utils;
 pub mod validation;
 mod state;
 mod main;
+mod merkle_tree;
diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
new file mode 100644
index 00000000..93570768
--- /dev/null
+++ b/src/merkle_tree.cairo
@@ -0,0 +1,17 @@
+use super::utils::double_sha256;
+
+pub fn merkle_root(ref txids: Array<u256>) -> u256 {
+    if txids.len() % 2 == 1 {
+        txids.append(*txids.at(txids.len() - 1));
+    }
+
+    let mut next_txids = ArrayTrait::new();
+    let mut i = 0;
+    let len = txids.len();
+    while i < len {
+        next_txids.append(double_sha256(*txids.at(i), *txids.at(i + 1)));
+        i += 2;
+    };
+
+    merkle_root(ref next_txids)
+}
diff --git a/src/utils.cairo b/src/utils.cairo
index 0e542db3..fc4010b0 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -1,5 +1,4 @@
-use core::traits::Into;
-use core::traits::TryInto;
+use core::sha256::{compute_sha256_byte_array, compute_sha256_u32_array};
 
 // Bitwise shift left for u256
 pub fn shl(value: u256, shift: u32) -> u256 {
@@ -34,3 +33,26 @@ pub fn fast_pow(base: u256, exp: u32) -> u256 {
         base = base * base;
     }
 }
+
+const TWO_POW_32: u128 = 0x100000000;
+const TWO_POW_64: u128 = 0x10000000000000000;
+const TWO_POW_96: u128 = 0x1000000000000000000000000;
+
+pub fn double_sha256(a: u256, b: u256) -> u256 {
+    let mut ba = Default::default();
+
+    ba.append_word(a.high.into(), 16);
+    ba.append_word(a.low.into(), 16);
+    ba.append_word(b.high.into(), 16);
+    ba.append_word(b.low.into(), 16);
+
+    let mut input1 = Default::default();
+    input1.append_span(compute_sha256_byte_array(@ba).span());
+
+    let [x0, x1, x2, x3, x4, x5, x6, x7] = compute_sha256_u32_array(input1, 0, 0);
+
+    u256 {
+        high: x0.into() * TWO_POW_96 + x1.into() * TWO_POW_64 + x2.into() * TWO_POW_32 + x3.into(),
+        low: x4.into() * TWO_POW_96 + x5.into() * TWO_POW_64 + x6.into() * TWO_POW_32 + x7.into(),
+    }
+}
diff --git a/src/validation.cairo b/src/validation.cairo
index ce17c749..177eae3b 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -1,4 +1,5 @@
-use super::utils::{shl, shr};
+use super::merkle_tree::merkle_root;
+use super::utils::{shl, shr, double_sha256};
 use super::state::{Block, ChainState, Transaction, UtreexoState};
 
 const MAX_TARGET: u256 = 0x00000000FFFF0000000000000000000000000000000000000000000000000000;
@@ -101,12 +102,6 @@ fn adjust_difficulty(self: @ChainState, block: @Block) -> (u32, u32) {
     (*self.current_target, *self.epoch_start_time)
 }
 
-fn validate_merkle_root(self: @ChainState, block: @Block) -> Result<(), ByteArray> {
-    // TODO: implement
-    Result::Ok(())
-}
-
-
 pub fn target_to_bits(target: u256) -> Result<u32, felt252> {
     if target == 0 {
         return Result::Err('Target is zero');
@@ -160,12 +155,7 @@ fn fee_and_merkle_root(self: @ChainState, block: @Block) -> Result<(u256, u256),
         total_fee += tx.fee();
     };
 
-    Result::Ok((total_fee, merkle_root(txids)))
-}
-
-fn merkle_root(txids: Array<u256>) -> u256 {
-    // TODO: implement
-    0
+    Result::Ok((total_fee, merkle_root(ref txids)))
 }
 
 fn validate_coinbase(block: @Block, total_fees: u256) -> Result<(), ByteArray> {

From 285467077456de464b0dcfe4c8ed421816ed10d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski?= <aundumla@gmail.com>
Date: Wed, 7 Aug 2024 23:48:34 +0200
Subject: [PATCH 02/23] draft of merkle tree

---
 src/merkle_tree.cairo | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index 93570768..8495b3b9 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -1,13 +1,18 @@
 use super::utils::double_sha256;
 
 pub fn merkle_root(ref txids: Array<u256>) -> u256 {
-    if txids.len() % 2 == 1 {
-        txids.append(*txids.at(txids.len() - 1));
+    let len = txids.len();
+    if len % 2 == 1 {
+        txids.append(*txids.at(len - 1));
+    } else {
+        // CVE-2012-2459 bug fix
+        assert!(
+            txids.at(len - 1) != txids.at(len - 2), "unexpected node duplication in merkle tree"
+        );
     }
 
     let mut next_txids = ArrayTrait::new();
     let mut i = 0;
-    let len = txids.len();
     while i < len {
         next_txids.append(double_sha256(*txids.at(i), *txids.at(i + 1)));
         i += 2;

From 2cc25eec07ac9a8ae18256ac6cbdf53d353d4be0 Mon Sep 17 00:00:00 2001
From: mubarak23 <mubarakaminu340@gmail.com>
Date: Thu, 8 Aug 2024 11:37:49 +0100
Subject: [PATCH 03/23] compute merkle root implementation

---
 src/lib.cairo         |  1 +
 src/merkle_tree.cairo | 88 +++++++++++++++++++++++++++++++++++++++++++
 src/utils.cairo       | 26 ++++++++++++-
 src/validation.cairo  | 49 ++----------------------
 4 files changed, 116 insertions(+), 48 deletions(-)
 create mode 100644 src/merkle_tree.cairo

diff --git a/src/lib.cairo b/src/lib.cairo
index ce41db81..201712a7 100644
--- a/src/lib.cairo
+++ b/src/lib.cairo
@@ -3,3 +3,4 @@ pub mod validation;
 
 mod state;
 mod main;
+mod merkle_tree;
diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
new file mode 100644
index 00000000..e04d3d9d
--- /dev/null
+++ b/src/merkle_tree.cairo
@@ -0,0 +1,88 @@
+use super::utils::double_sha256;
+
+pub fn merkle_root(ref txids: Array<u256>) -> u256 {
+    let len = txids.len();
+    if len % 2 == 1 {
+        txids.append(*txids.at(len - 1));
+    } else {
+        // CVE-2012-2459 bug fix
+        assert!(
+            txids.at(len - 1) != txids.at(len - 2), "unexpected node duplication in merkle tree"
+        );
+    }
+
+    let mut next_txids = ArrayTrait::new();
+    let mut i = 0;
+    while i < len {
+        next_txids.append(double_sha256(*txids.at(i), *txids.at(i + 1)));
+        i += 2;
+    };
+
+    merkle_root(ref next_txids)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{merkle_root};
+    use starknet::core::types::FieldElement;
+
+    #[test]
+    fn test_merkle_root() {
+        let txids = vec![
+            FieldElement::from_hex_be(
+                "50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "ec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "d94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "c4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "d4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "b5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351"
+            )
+                .unwrap(),
+            FieldElement::from_hex_be(
+                "f9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f"
+            )
+                .unwrap(),
+        ];
+        let expected_merkle_root = FieldElement::from_hex_be(
+            "17663ab10c2e13d92dccb4514b05b18815f5f38af1f21e06931c71d62b36d8af"
+        )
+            .unwrap();
+        assert_eq!(merkle_root(txids), expected_merkle_root);
+    }
+}
+
diff --git a/src/utils.cairo b/src/utils.cairo
index 0e542db3..fc4010b0 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -1,5 +1,4 @@
-use core::traits::Into;
-use core::traits::TryInto;
+use core::sha256::{compute_sha256_byte_array, compute_sha256_u32_array};
 
 // Bitwise shift left for u256
 pub fn shl(value: u256, shift: u32) -> u256 {
@@ -34,3 +33,26 @@ pub fn fast_pow(base: u256, exp: u32) -> u256 {
         base = base * base;
     }
 }
+
+const TWO_POW_32: u128 = 0x100000000;
+const TWO_POW_64: u128 = 0x10000000000000000;
+const TWO_POW_96: u128 = 0x1000000000000000000000000;
+
+pub fn double_sha256(a: u256, b: u256) -> u256 {
+    let mut ba = Default::default();
+
+    ba.append_word(a.high.into(), 16);
+    ba.append_word(a.low.into(), 16);
+    ba.append_word(b.high.into(), 16);
+    ba.append_word(b.low.into(), 16);
+
+    let mut input1 = Default::default();
+    input1.append_span(compute_sha256_byte_array(@ba).span());
+
+    let [x0, x1, x2, x3, x4, x5, x6, x7] = compute_sha256_u32_array(input1, 0, 0);
+
+    u256 {
+        high: x0.into() * TWO_POW_96 + x1.into() * TWO_POW_64 + x2.into() * TWO_POW_32 + x3.into(),
+        low: x4.into() * TWO_POW_96 + x5.into() * TWO_POW_64 + x6.into() * TWO_POW_32 + x7.into(),
+    }
+}
diff --git a/src/validation.cairo b/src/validation.cairo
index 3ce23b23..177eae3b 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -1,5 +1,6 @@
+use super::merkle_tree::merkle_root;
+use super::utils::{shl, shr, double_sha256};
 use super::state::{Block, ChainState, Transaction, UtreexoState};
-use super::utils::{shl, shr};
 
 const MAX_TARGET: u256 = 0x00000000FFFF0000000000000000000000000000000000000000000000000000;
 
@@ -101,45 +102,6 @@ fn adjust_difficulty(self: @ChainState, block: @Block) -> (u32, u32) {
     (*self.current_target, *self.epoch_start_time)
 }
 
-fn validate_merkle_root(self: @ChainState, block: @Block) -> Result<(), ByteArray> {
-    // TODO: implement
-    Result::Ok(())
-}
-
-// Helper functions
-pub fn bits_to_target(bits: u32) -> Result<u256, felt252> {
-    // Extract exponent and mantissa
-    let exponent: u32 = (bits / 0x1000000);
-    let mantissa: u32 = bits & 0x00FFFFFF;
-
-    // Check if mantissa is valid (should be less than 0x1000000)
-    if mantissa > 0x7FFFFF && exponent != 0 {
-        return Result::Err('Invalid mantissa');
-    }
-
-    // Calculate the full target value
-    let mut target: u256 = mantissa.into();
-
-    if exponent == 0 {
-        // Special case: exponent 0 means we use the mantissa as-is
-        return Result::Ok(target);
-    } else if exponent <= 3 {
-        // For exponents 1, 2, and 3, divide by 256^(3 - exponent) i.e right shift
-        let shift = 8 * (3 - exponent);
-        target = shr(target, shift);
-    } else {
-        let shift = 8 * (exponent - 3);
-        target = shl(target, shift);
-    }
-
-    // Ensure the target doesn't exceed the maximum allowed value
-    if target > MAX_TARGET {
-        return Result::Err('Target exceeds maximum');
-    }
-
-    Result::Ok(target)
-}
-
 pub fn target_to_bits(target: u256) -> Result<u32, felt252> {
     if target == 0 {
         return Result::Err('Target is zero');
@@ -193,12 +155,7 @@ fn fee_and_merkle_root(self: @ChainState, block: @Block) -> Result<(u256, u256),
         total_fee += tx.fee();
     };
 
-    Result::Ok((total_fee, merkle_root(txids)))
-}
-
-fn merkle_root(txids: Array<u256>) -> u256 {
-    // TODO: implement
-    0
+    Result::Ok((total_fee, merkle_root(ref txids)))
 }
 
 fn validate_coinbase(block: @Block, total_fees: u256) -> Result<(), ByteArray> {

From f9fc168c37e26dfab2165cccf2907650167fddd5 Mon Sep 17 00:00:00 2001
From: mubarak23 <mubarakaminu340@gmail.com>
Date: Thu, 8 Aug 2024 14:37:27 +0100
Subject: [PATCH 04/23] fix changes

---
 src/merkle_tree.cairo | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index e04d3d9d..66836d00 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -28,7 +28,8 @@ mod tests {
 
     #[test]
     fn test_merkle_root() {
-        let txids = vec![
+
+        let txids = array![
             FieldElement::from_hex_be(
                 "50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38"
             )
@@ -79,7 +80,7 @@ mod tests {
                 .unwrap(),
         ];
         let expected_merkle_root = FieldElement::from_hex_be(
-            "17663ab10c2e13d92dccb4514b05b18815f5f38af1f21e06931c71d62b36d8af"
+            "0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256"
         )
             .unwrap();
         assert_eq!(merkle_root(txids), expected_merkle_root);

From 651c3148ea6a36da432d7cdcb25f877bf4df1e0a Mon Sep 17 00:00:00 2001
From: mubarak23 <mubarakaminu340@gmail.com>
Date: Thu, 8 Aug 2024 18:55:22 +0100
Subject: [PATCH 05/23] use u256 Array as transaction ids data in test

---
 src/merkle_tree.cairo | 70 ++++++++++---------------------------------
 1 file changed, 16 insertions(+), 54 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index 533fb8ca..830d40e3 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -30,60 +30,22 @@ mod tests {
     #[test]
     fn test_merkle_root() {
 
-        let txids = array![
-            FieldElement::from_hex_be(
-                "50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "ec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "d94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "c4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "d4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "b5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351"
-            )
-                .unwrap(),
-            FieldElement::from_hex_be(
-                "f9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f"
-            )
-                .unwrap(),
-        ];
-        let expected_merkle_root = FieldElement::from_hex_be(
-            "0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256"
-        )
-            .unwrap();
+         let txids =  array![0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256,
+          0x96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6_u256, 
+          0x65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4_u256,
+          0x1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815_u256,
+          0xec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712_u256,
+          0x5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50_u256,
+          0x0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615_256,
+          0xd94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711_u256,
+          0xc4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a_u256,
+          0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
+          0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
+          0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
+          ]
+     
+        let expected_merkle_root = "0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256"
+       
         assert_eq!(merkle_root(txids), expected_merkle_root);
     }
 }

From 18f05dbc337ddefda149460f342537e68378d360 Mon Sep 17 00:00:00 2001
From: mubarak23 <mubarakaminu340@gmail.com>
Date: Thu, 8 Aug 2024 19:03:19 +0100
Subject: [PATCH 06/23] fix end of line

---
 src/merkle_tree.cairo | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index 830d40e3..ca22fc78 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -42,9 +42,9 @@ mod tests {
           0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
           0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
           0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
-          ]
+          ];
      
-        let expected_merkle_root = "0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256"
+        let expected_merkle_root = "0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256";
        
         assert_eq!(merkle_root(txids), expected_merkle_root);
     }

From db66e5d5b3e80b7748c5991b64d21001835b25c9 Mon Sep 17 00:00:00 2001
From: mubarak23 <mubarakaminu340@gmail.com>
Date: Thu, 8 Aug 2024 21:43:43 +0100
Subject: [PATCH 07/23] use ref in txids

---
 src/merkle_tree.cairo | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index c922e916..a770ebdd 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -24,7 +24,7 @@ pub fn merkle_root(ref txids: Array<u256>) -> u256 {
 #[cfg(test)]
 mod tests {
     use super::{merkle_root};
-    use starknet::core::types::FieldElement;
+   
 
     #[test]
     fn test_merkle_root() {
@@ -45,6 +45,6 @@ mod tests {
      
         let expected_merkle_root = 0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256;
        
-        assert_eq!(merkle_root(txids), expected_merkle_root);
+        assert_eq!(merkle_root(ref txids), expected_merkle_root);
     }
 }

From 8ecb8cc3db1bb6f32adb198ed366feb5f4b7fdec Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 12:29:22 +0200
Subject: [PATCH 08/23] make shl/shr and fastpow generics

---
 src/utils.cairo      | 94 ++++++++++++++++++++++++++++++++++++--------
 src/validation.cairo | 12 +++---
 2 files changed, 83 insertions(+), 23 deletions(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index 0e542db3..a2de7942 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -1,34 +1,94 @@
-use core::traits::Into;
-use core::traits::TryInto;
+use core::num::traits::{Zero, One, BitSize};
+use core::panic_with_felt252;
+use core::starknet::secp256_trait::Secp256PointTrait;
 
-// Bitwise shift left for u256
-pub fn shl(value: u256, shift: u32) -> u256 {
-    value * fast_pow(2.into(), shift.into())
+
+pub trait Bitshift<T, U> {
+    fn shl(self: T, shift: U) -> T;
+    fn shr(self: T, shift: U) -> T;
 }
 
-// Bitwise shift right for u256
-pub fn shr(value: u256, shift: u32) -> u256 {
-    value / fast_pow(2.into(), shift.into())
+pub impl BitshiftImpl<
+    T,
+    U,
+    +Zero<T>,
+    +Zero<U>,
+    +One<T>,
+    +One<U>,
+    +Add<T>,
+    +Add<U>,
+    +Sub<T>,
+    +Sub<U>,
+    +Div<T>,
+    +Mul<T>,
+    +Rem<U>,
+    +Div<U>,
+    +Copy<T>,
+    +Copy<U>,
+    +Drop<T>,
+    +Drop<U>,
+    +PartialOrd<T>,
+    +PartialOrd<U>,
+    +PartialEq<U>,
+    +BitSize<T>,
+    +TryInto<usize, T>,
+    +Into<usize, U>
+> of Bitshift<T, U> {
+    fn shl(self: T, shift: U) -> T {
+        if shift > BitSize::<T>::bits().into() - One::one() {
+            panic_with_felt252('mul Overflow');
+        }
+        let two = One::one() + One::one();
+        self * fast_pow(two, shift)
+    }
+
+    fn shr(self: T, shift: U) -> T {
+        if shift > BitSize::<T>::bits().try_into().unwrap() - One::one() {
+            panic_with_felt252('mul Overflow');
+        }
+        let two = One::one() + One::one();
+        self / fast_pow(two, shift)
+    }
 }
 
 // Fast exponentiation using the square-and-multiply algorithm
 // Reference:
 // https://github.com/keep-starknet-strange/alexandria/blob/bcdca70afdf59c9976148e95cebad5cf63d75a7f/packages/math/src/fast_power.cairo#L12
-pub fn fast_pow(base: u256, exp: u32) -> u256 {
-    if exp == 0 {
-        return 1_u256;
+pub fn fast_pow<
+    T,
+    U,
+    +Copy<U>,
+    +Copy<T>,
+    +Drop<T>,
+    +Drop<U>,
+    +Zero<T>,
+    +One<T>,
+    +Zero<U>,
+    +One<U>,
+    +PartialEq<U>,
+    +Add<U>,
+    +Mul<T>,
+    +Rem<U>,
+    +Div<U>
+>(
+    base: T, exp: U
+) -> T {
+    if exp == Zero::zero() {
+        return Zero::zero();
     }
 
-    let mut res: u256 = 1_u256;
-    let mut base: u256 = base;
-    let mut exp: u32 = exp;
+    let mut res: T = One::one();
+    let mut base: T = base;
+    let mut exp: U = exp;
+
+    let two: U = One::one() + One::one();
 
     loop {
-        if exp % 2 == 1 {
+        if exp % two == One::one() {
             res = res * base;
         }
-        exp = exp / 2;
-        if exp == 0 {
+        exp = exp / two;
+        if exp == Zero::zero() {
             break res;
         }
         base = base * base;
diff --git a/src/validation.cairo b/src/validation.cairo
index 3ce23b23..952d0790 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -1,5 +1,5 @@
 use super::state::{Block, ChainState, Transaction, UtreexoState};
-use super::utils::{shl, shr};
+use super::utils::Bitshift;
 
 const MAX_TARGET: u256 = 0x00000000FFFF0000000000000000000000000000000000000000000000000000;
 
@@ -126,10 +126,10 @@ pub fn bits_to_target(bits: u32) -> Result<u256, felt252> {
     } else if exponent <= 3 {
         // For exponents 1, 2, and 3, divide by 256^(3 - exponent) i.e right shift
         let shift = 8 * (3 - exponent);
-        target = shr(target, shift);
+        target = Bitshift::shr(target, shift);
     } else {
         let shift = 8 * (exponent - 3);
-        target = shl(target, shift);
+        target = Bitshift::shl(target, shift);
     }
 
     // Ensure the target doesn't exceed the maximum allowed value
@@ -154,12 +154,12 @@ pub fn target_to_bits(target: u256) -> Result<u32, felt252> {
     let mut compact = target;
 
     // Count leading zero bytes by finding the first non-zero byte
-    while size > 1 && shr(compact, (size - 1) * 8) == 0 {
+    while size > 1 && Bitshift::shr(compact, (size - 1) * 8) == 0 {
         size -= 1;
     };
 
     // Extract mantissa (most significant 3 bytes)
-    let mut mantissa: u32 = shr(compact, (size - 3) * 8).try_into().unwrap();
+    let mut mantissa: u32 = Bitshift::shr(compact, (size - 3) * 8).try_into().unwrap();
 
     // Normalize
     if mantissa > 0x7fffff {
@@ -179,7 +179,7 @@ pub fn target_to_bits(target: u256) -> Result<u32, felt252> {
     let size_u256: u256 = size.into();
 
     // Combine size and mantissa
-    let result: u32 = (shl(size_u256, 24) + mantissa.into()).try_into().unwrap();
+    let result: u32 = (Bitshift::shl(size_u256, 24_u32) + mantissa.into()).try_into().unwrap();
 
     Result::Ok(result)
 }

From 25b1a26a68693202633a3fe1272b0c238a72a712 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 12:34:19 +0200
Subject: [PATCH 09/23] fix

---
 src/utils.cairo | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index a2de7942..f908f3c5 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -31,7 +31,6 @@ pub impl BitshiftImpl<
     +PartialOrd<U>,
     +PartialEq<U>,
     +BitSize<T>,
-    +TryInto<usize, T>,
     +Into<usize, U>
 > of Bitshift<T, U> {
     fn shl(self: T, shift: U) -> T {

From d90002bcd0eeb1bf152557b42ac6619d0442aee3 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 12:38:21 +0200
Subject: [PATCH 10/23] merge main

---
 src/validation.cairo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/validation.cairo b/src/validation.cairo
index 1d40d1b9..b6ec19cc 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -219,7 +219,7 @@ fn validate_coinbase(block: @Block, total_fees: u256) -> Result<(), ByteArray> {
 
 // Return BTC reward in SATS
 fn compute_block_reward(block_height: u32) -> u64 {
-    shr(5000000000, block_height / 210_000).try_into().unwrap()
+    Bitshift::shr(5000000000_u256, block_height / 210_000).try_into().unwrap()
 }
 #[cfg(test)]
 mod tests {

From 0af861fd1c0134de156bddacaaf1d3c6d7783c5c Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 12:40:51 +0200
Subject: [PATCH 11/23] remove some imports

---
 src/validation.cairo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/validation.cairo b/src/validation.cairo
index b6ec19cc..37c003a4 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -225,7 +225,7 @@ fn compute_block_reward(block_height: u32) -> u64 {
 mod tests {
     use super::{
         validate_target, validate_timestamp, validate_proof_of_work, compute_block_reward,
-        compute_total_work, compute_work_from_target, shr, shl, REWARD_INITIAL, POW_SATS_AMOUNT
+        compute_total_work, compute_work_from_target, REWARD_INITIAL, POW_SATS_AMOUNT
     };
     use super::{Block, ChainState, UtreexoState};
     use super::super::state::{Header, Transaction, TxIn, TxOut};

From 651b563880b459fc902a1cc463b9a1ec8fd3f025 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 12:51:43 +0200
Subject: [PATCH 12/23] solve last bug

---
 src/utils.cairo      | 3 ++-
 src/validation.cairo | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index f908f3c5..94e60785 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -45,6 +45,7 @@ pub impl BitshiftImpl<
         if shift > BitSize::<T>::bits().try_into().unwrap() - One::one() {
             panic_with_felt252('mul Overflow');
         }
+
         let two = One::one() + One::one();
         self / fast_pow(two, shift)
     }
@@ -73,7 +74,7 @@ pub fn fast_pow<
     base: T, exp: U
 ) -> T {
     if exp == Zero::zero() {
-        return Zero::zero();
+        return One::one();
     }
 
     let mut res: T = One::one();
diff --git a/src/validation.cairo b/src/validation.cairo
index 37c003a4..eb2f646d 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -219,7 +219,7 @@ fn validate_coinbase(block: @Block, total_fees: u256) -> Result<(), ByteArray> {
 
 // Return BTC reward in SATS
 fn compute_block_reward(block_height: u32) -> u64 {
-    Bitshift::shr(5000000000_u256, block_height / 210_000).try_into().unwrap()
+    Bitshift::shr(5000000000_u256, (block_height / 210000_u32)).try_into().unwrap()
 }
 #[cfg(test)]
 mod tests {

From 210658f05319d732d560fe9108e392b137a844e9 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 13:00:04 +0200
Subject: [PATCH 13/23] improve generic constraints order + overall nits

---
 src/utils.cairo      | 19 ++++++++-----------
 src/validation.cairo | 14 ++++++++++----
 2 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index 94e60785..e4d69e8c 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -2,7 +2,6 @@ use core::num::traits::{Zero, One, BitSize};
 use core::panic_with_felt252;
 use core::starknet::secp256_trait::Secp256PointTrait;
 
-
 pub trait Bitshift<T, U> {
     fn shl(self: T, shift: U) -> T;
     fn shr(self: T, shift: U) -> T;
@@ -17,17 +16,15 @@ pub impl BitshiftImpl<
     +One<U>,
     +Add<T>,
     +Add<U>,
-    +Sub<T>,
     +Sub<U>,
     +Div<T>,
     +Mul<T>,
-    +Rem<U>,
     +Div<U>,
+    +Rem<U>,
     +Copy<T>,
     +Copy<U>,
     +Drop<T>,
     +Drop<U>,
-    +PartialOrd<T>,
     +PartialOrd<U>,
     +PartialEq<U>,
     +BitSize<T>,
@@ -57,19 +54,19 @@ pub impl BitshiftImpl<
 pub fn fast_pow<
     T,
     U,
-    +Copy<U>,
-    +Copy<T>,
-    +Drop<T>,
-    +Drop<U>,
     +Zero<T>,
-    +One<T>,
     +Zero<U>,
+    +One<T>,
     +One<U>,
-    +PartialEq<U>,
     +Add<U>,
     +Mul<T>,
     +Rem<U>,
-    +Div<U>
+    +Div<U>,
+    +Copy<T>,
+    +Copy<U>,
+    +Drop<T>,
+    +Drop<U>,
+    +PartialEq<U>,
 >(
     base: T, exp: U
 ) -> T {
diff --git a/src/validation.cairo b/src/validation.cairo
index eb2f646d..315599db 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -221,14 +221,16 @@ fn validate_coinbase(block: @Block, total_fees: u256) -> Result<(), ByteArray> {
 fn compute_block_reward(block_height: u32) -> u64 {
     Bitshift::shr(5000000000_u256, (block_height / 210000_u32)).try_into().unwrap()
 }
+
+
 #[cfg(test)]
 mod tests {
+    use raito::state::{Header, Transaction, TxIn, TxOut};
     use super::{
-        validate_target, validate_timestamp, validate_proof_of_work, compute_block_reward,
-        compute_total_work, compute_work_from_target, REWARD_INITIAL, POW_SATS_AMOUNT
+        Block, ChainState, UtreexoState, REWARD_INITIAL, POW_SATS_AMOUNT, compute_block_reward,
+        compute_work_from_target, compute_total_work, validate_proof_of_work, validate_target,
+        validate_timestamp
     };
-    use super::{Block, ChainState, UtreexoState};
-    use super::super::state::{Header, Transaction, TxIn, TxOut};
 
     #[test]
     fn test_validate_target() {
@@ -298,6 +300,7 @@ mod tests {
         let work = compute_work_from_target(target);
         assert(expected_work == work, 'Failed to compute target');
     }
+
     #[test]
     fn test_compute_work_from_target2() {
         let expected_work = 0x26d946e509ac00026d;
@@ -305,6 +308,7 @@ mod tests {
         let work = compute_work_from_target(target);
         assert(expected_work == work, 'Failed to compute target');
     }
+
     #[test]
     fn test_compute_work_from_target3() {
         let expected_work = 0xe10005c64415f04ef3e387b97db388404db9fdfaab2b1918f6783471d;
@@ -312,6 +316,7 @@ mod tests {
         let work = compute_work_from_target(target);
         assert(expected_work == work, 'Failed to compute target');
     }
+
     #[test]
     fn test_compute_work_from_target4() {
         let expected_work = 0x1c040c95a099201bcaf85db4e7f2e21e18707c8d55a887643b95afb2f;
@@ -319,6 +324,7 @@ mod tests {
         let work = compute_work_from_target(target);
         assert(expected_work == work, 'Failed to compute target');
     }
+
     #[test]
     fn test_compute_work_from_target5() {
         let expected_work = 0x21809b468faa88dbe34f;

From 89ea94897ef067d3984e277daa816f4ad7018f05 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 13:09:13 +0200
Subject: [PATCH 14/23] dont panic but return 0 if shift > Bitsize<T>

---
 src/utils.cairo | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index e4d69e8c..5f1ca6d6 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -32,7 +32,7 @@ pub impl BitshiftImpl<
 > of Bitshift<T, U> {
     fn shl(self: T, shift: U) -> T {
         if shift > BitSize::<T>::bits().into() - One::one() {
-            panic_with_felt252('mul Overflow');
+            return Zero::zero();
         }
         let two = One::one() + One::one();
         self * fast_pow(two, shift)
@@ -40,7 +40,7 @@ pub impl BitshiftImpl<
 
     fn shr(self: T, shift: U) -> T {
         if shift > BitSize::<T>::bits().try_into().unwrap() - One::one() {
-            panic_with_felt252('mul Overflow');
+            return Zero::zero();
         }
 
         let two = One::one() + One::one();

From 00b51db742efb506d283bcbfaf065581f345a534 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 13:13:15 +0200
Subject: [PATCH 15/23] remove unused panicwithfelt import

---
 src/utils.cairo | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index 5f1ca6d6..d462e88c 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -1,5 +1,4 @@
 use core::num::traits::{Zero, One, BitSize};
-use core::panic_with_felt252;
 use core::starknet::secp256_trait::Secp256PointTrait;
 
 pub trait Bitshift<T, U> {

From 13511174f0d78cd2779b2301e3e753c74e2a7631 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 13:31:20 +0200
Subject: [PATCH 16/23] remove trait

---
 src/utils.cairo      | 57 +++++++++++++++++++++++++++++---------------
 src/validation.cairo | 14 +++++------
 2 files changed, 45 insertions(+), 26 deletions(-)

diff --git a/src/utils.cairo b/src/utils.cairo
index d462e88c..f50e5c40 100644
--- a/src/utils.cairo
+++ b/src/utils.cairo
@@ -1,12 +1,38 @@
 use core::num::traits::{Zero, One, BitSize};
 use core::starknet::secp256_trait::Secp256PointTrait;
 
-pub trait Bitshift<T, U> {
-    fn shl(self: T, shift: U) -> T;
-    fn shr(self: T, shift: U) -> T;
+pub fn shl<
+    T,
+    U,
+    +Zero<T>,
+    +Zero<U>,
+    +One<T>,
+    +One<U>,
+    +Add<T>,
+    +Add<U>,
+    +Sub<U>,
+    +Mul<T>,
+    +Div<U>,
+    +Rem<U>,
+    +Copy<T>,
+    +Copy<U>,
+    +Drop<T>,
+    +Drop<U>,
+    +PartialOrd<U>,
+    +PartialEq<U>,
+    +BitSize<T>,
+    +Into<usize, U>
+>(
+    self: T, shift: U,
+) -> T {
+    if shift > BitSize::<T>::bits().into() - One::one() {
+        return Zero::zero();
+    }
+    let two = One::one() + One::one();
+    self * fast_pow(two, shift)
 }
 
-pub impl BitshiftImpl<
+pub fn shr<
     T,
     U,
     +Zero<T>,
@@ -28,25 +54,18 @@ pub impl BitshiftImpl<
     +PartialEq<U>,
     +BitSize<T>,
     +Into<usize, U>
-> of Bitshift<T, U> {
-    fn shl(self: T, shift: U) -> T {
-        if shift > BitSize::<T>::bits().into() - One::one() {
-            return Zero::zero();
-        }
-        let two = One::one() + One::one();
-        self * fast_pow(two, shift)
+>(
+    self: T, shift: U
+) -> T {
+    if shift > BitSize::<T>::bits().try_into().unwrap() - One::one() {
+        return Zero::zero();
     }
 
-    fn shr(self: T, shift: U) -> T {
-        if shift > BitSize::<T>::bits().try_into().unwrap() - One::one() {
-            return Zero::zero();
-        }
-
-        let two = One::one() + One::one();
-        self / fast_pow(two, shift)
-    }
+    let two = One::one() + One::one();
+    self / fast_pow(two, shift)
 }
 
+
 // Fast exponentiation using the square-and-multiply algorithm
 // Reference:
 // https://github.com/keep-starknet-strange/alexandria/blob/bcdca70afdf59c9976148e95cebad5cf63d75a7f/packages/math/src/fast_power.cairo#L12
diff --git a/src/validation.cairo b/src/validation.cairo
index 315599db..0765b1b5 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -1,5 +1,5 @@
 use super::state::{Block, ChainState, Transaction, UtreexoState};
-use super::utils::Bitshift;
+use super::utils::{shr, shl};
 
 const MAX_TARGET: u256 = 0x00000000FFFF0000000000000000000000000000000000000000000000000000;
 pub const REWARD_INITIAL: u256 = 50; // 50 BTC in satoshis =>  5000000000 SATS
@@ -137,10 +137,10 @@ pub fn bits_to_target(bits: u32) -> Result<u256, felt252> {
     } else if exponent <= 3 {
         // For exponents 1, 2, and 3, divide by 256^(3 - exponent) i.e right shift
         let shift = 8 * (3 - exponent);
-        target = Bitshift::shr(target, shift);
+        target = shr(target, shift);
     } else {
         let shift = 8 * (exponent - 3);
-        target = Bitshift::shl(target, shift);
+        target = shl(target, shift);
     }
 
     // Ensure the target doesn't exceed the maximum allowed value
@@ -165,12 +165,12 @@ pub fn target_to_bits(target: u256) -> Result<u32, felt252> {
     let mut compact = target;
 
     // Count leading zero bytes by finding the first non-zero byte
-    while size > 1 && Bitshift::shr(compact, (size - 1) * 8) == 0 {
+    while size > 1 && shr(compact, (size - 1) * 8) == 0 {
         size -= 1;
     };
 
     // Extract mantissa (most significant 3 bytes)
-    let mut mantissa: u32 = Bitshift::shr(compact, (size - 3) * 8).try_into().unwrap();
+    let mut mantissa: u32 = shr(compact, (size - 3) * 8).try_into().unwrap();
 
     // Normalize
     if mantissa > 0x7fffff {
@@ -190,7 +190,7 @@ pub fn target_to_bits(target: u256) -> Result<u32, felt252> {
     let size_u256: u256 = size.into();
 
     // Combine size and mantissa
-    let result: u32 = (Bitshift::shl(size_u256, 24_u32) + mantissa.into()).try_into().unwrap();
+    let result: u32 = (shl(size_u256, 24_u32) + mantissa.into()).try_into().unwrap();
 
     Result::Ok(result)
 }
@@ -219,7 +219,7 @@ fn validate_coinbase(block: @Block, total_fees: u256) -> Result<(), ByteArray> {
 
 // Return BTC reward in SATS
 fn compute_block_reward(block_height: u32) -> u64 {
-    Bitshift::shr(5000000000_u256, (block_height / 210000_u32)).try_into().unwrap()
+    shr(5000000000_u256, (block_height / 210000_u32)).try_into().unwrap()
 }
 
 

From 8197295693834593f3d5152dca4755bd0f2542a8 Mon Sep 17 00:00:00 2001
From: TAdev0 <angles.tristan@protonmail.com>
Date: Fri, 9 Aug 2024 13:32:21 +0200
Subject: [PATCH 17/23] keep alphabetic order for imports

---
 src/validation.cairo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/validation.cairo b/src/validation.cairo
index 0765b1b5..19f3bf7d 100644
--- a/src/validation.cairo
+++ b/src/validation.cairo
@@ -1,5 +1,5 @@
 use super::state::{Block, ChainState, Transaction, UtreexoState};
-use super::utils::{shr, shl};
+use super::utils::{shl, shr};
 
 const MAX_TARGET: u256 = 0x00000000FFFF0000000000000000000000000000000000000000000000000000;
 pub const REWARD_INITIAL: u256 = 50; // 50 BTC in satoshis =>  5000000000 SATS

From 178bc9e600b9c2ad3004cd806a975a1da60545a8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski=20=40=20StarkWare?=
 <aundumla@gmail.com>
Date: Fri, 9 Aug 2024 14:03:55 +0200
Subject: [PATCH 18/23] fmt

---
 src/merkle_tree.cairo | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index a770ebdd..d1020477 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -29,18 +29,18 @@ mod tests {
     #[test]
     fn test_merkle_root() {
          let txids =  array![
-          0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256,
-          0x96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6_u256, 
-          0x65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4_u256,
-          0x1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815_u256,
-          0xec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712_u256,
-          0x5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50_u256,
-          0x0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615_u256,
-          0xd94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711_u256,
-          0xc4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a_u256,
-          0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
-          0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
-          0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
+              0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256,
+              0x96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6_u256, 
+              0x65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4_u256,
+              0x1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815_u256,
+              0xec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712_u256,
+              0x5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50_u256,
+              0x0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615_u256,
+              0xd94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711_u256,
+              0xc4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a_u256,
+              0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
+              0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
+              0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
           ];
      
         let expected_merkle_root = 0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256;

From 1d75d64d97c7b5b9aefa315f4a02d8f2ead22912 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski=20=40=20StarkWare?=
 <aundumla@gmail.com>
Date: Fri, 9 Aug 2024 14:06:52 +0200
Subject: [PATCH 19/23] fmt

---
 src/merkle_tree.cairo | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index d1020477..89ede39c 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -28,20 +28,20 @@ mod tests {
 
     #[test]
     fn test_merkle_root() {
-         let txids =  array![
-              0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256,
-              0x96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6_u256, 
-              0x65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4_u256,
-              0x1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815_u256,
-              0xec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712_u256,
-              0x5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50_u256,
-              0x0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615_u256,
-              0xd94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711_u256,
-              0xc4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a_u256,
-              0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
-              0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
-              0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
-          ];
+        let txids =  array![
+            0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256,
+            0x96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6_u256, 
+            0x65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4_u256,
+            0x1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815_u256,
+            0xec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712_u256,
+            0x5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50_u256,
+            0x0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615_u256,
+            0xd94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711_u256,
+            0xc4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a_u256,
+            0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
+            0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
+            0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
+        ];
      
         let expected_merkle_root = 0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256;
        

From ac600878e3c9ba356e5e0522a872679758153dcb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski?= <aundumla@gmail.com>
Date: Fri, 9 Aug 2024 14:49:12 +0200
Subject: [PATCH 20/23] fix merkle_tree tests

---
 src/merkle_tree.cairo | 76 +++++++++++++++++++++++++++++++++----------
 1 file changed, 58 insertions(+), 18 deletions(-)

diff --git a/src/merkle_tree.cairo b/src/merkle_tree.cairo
index 89ede39c..fa77d06f 100644
--- a/src/merkle_tree.cairo
+++ b/src/merkle_tree.cairo
@@ -2,6 +2,11 @@ use super::utils::double_sha256;
 
 pub fn merkle_root(ref txids: Array<u256>) -> u256 {
     let len = txids.len();
+
+    if len == 1 {
+        return *txids.at(0);
+    }
+
     if len % 2 == 1 {
         txids.append(*txids.at(len - 1));
     } else {
@@ -24,27 +29,62 @@ pub fn merkle_root(ref txids: Array<u256>) -> u256 {
 #[cfg(test)]
 mod tests {
     use super::{merkle_root};
-   
 
     #[test]
-    fn test_merkle_root() {
-        let txids =  array![
-            0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256,
-            0x96b8787b1e3abed802cff132c891c2e511edd200b08baa9eb7d8942d7c5423c6_u256, 
-            0x65e5a4862b807c83b588e0f4122d4ca2d46691d17a1ec1ebce4485dccc3380d4_u256,
-            0x1ee9441ddde02f8ffb910613cd509adbc21282c6e34728599f3ae75e972fb815_u256,
-            0xec950fc02f71fc06ed71afa4d2c49fcba04777f353a001b0bba9924c63cfe712_u256,
-            0x5d874040a77de7182f7a68bf47c02898f519cb3b58092b79fa2cff614a0f4d50_u256,
-            0x0a1c958af3e30ad07f659f44f708f8648452d1427463637b9039e5b721699615_u256,
-            0xd94d24d2dcaac111f5f638983122b0e55a91aeb999e0e4d58e0952fa346a1711_u256,
-            0xc4709bc9f860e5dff01b5fc7b53fb9deecc622214aba710d495bccc7f860af4a_u256,
-            0xd4ed5f5e4334c0a4ccce6f706f3c9139ac0f6d2af3343ad3fae5a02fee8df542_u256,
-            0xb5aed07505677c8b1c6703742f4558e993d7984dc03d2121d3712d81ee067351_u256,
-            0xf9a14bf211c857f61ff9a1de95fc902faebff67c5d4898da8f48c9d306f1f80f_u256
+    #[available_gas(100000000)]
+    fn test_merkle_root_01() {
+        let mut txids = array![
+            0xacd9825be8bece7782ec746a80b52f44d6a8af41c63dbab59b03e29558469682_u256,
+        ];
+
+        let expected_merkle_root =
+            0xacd9825be8bece7782ec746a80b52f44d6a8af41c63dbab59b03e29558469682_u256;
+
+        assert_eq!(merkle_root(ref txids), expected_merkle_root);
+    }
+
+    #[test]
+    #[available_gas(100000000)]
+    fn test_merkle_root_02() {
+        let mut txids = array![
+            0x8710b2819a369672a2bce3d5270e7ae0ea59be2f7ce7f9078341b389098953e0_u256,
+            0x64efde3a3f3531569cdab031bb31cfeb5c2d8cba62ae1ca5b2913b4ef643fd49_u256
         ];
-     
-        let expected_merkle_root = 0x50ba87bdd484f07c8c55f76a22982f987c0465fdc345381b4634a70dc0ea0b38_u256;
-       
+
+        let expected_merkle_root =
+            0x20dadaf81170decafec4b025366b75284dbe31dd42c8da5d25ff62fc4bff5d03_u256;
+
+        assert_eq!(merkle_root(ref txids), expected_merkle_root);
+    }
+
+    #[test]
+    #[available_gas(100000000)]
+    fn test_merkle_root_03() {
+        let mut txids = array![
+            0xd47e03351ee65f73321b684832edc4c840a1fe4bbd04bdb66a8328e5c7796e21_u256,
+            0xbf304002ea77842b32dc91f1efe681a5a7909f4200e658e2ef2beb2a821101b9_u256,
+            0x397bdf0bf5a8798f5b10bd95c70bb4a3f42ca14a9a837a4a54cd7de525dc0225_u256,
+            0xd6ce148117a1cd094cdd5303ae0896cae1b29ad010b6cb0f3d43fa99b5e2c2f7_u256,
+            0x7d5ad03ebf001acb47aafdf4915e86b7368ed3183c1e95f47280d81bb4ef91f8_u256,
+            0x69cf63b266ebc862bd4d1a01473703c14bdd3a620f93ec323144c7d2c54529a0_u256,
+            0x155be8f959b0187d7528a1ff11b3450690047aa96dbbb29a1ae3832b237c8179_u256,
+            0x727d5fbed290d645ced8776c9031d7c3438454b5faf1f5dc0200dbe84f8e6035_u256,
+            0xc6056c6021081150a86c092f6785955f757024f41472ad4b0cfd9dd39db8b4a2_u256,
+            0x83f26f37bb715ec325f25544b6d7ae920fcc073c146c8dd12fbbde31a7ae1d2f_u256,
+            0xd39bc02ef2b2c5afdb7807b0162b573648d9264d5e9872dbf26a7d480de301cd_u256,
+            0x3dc087cb9e9d66c4d3e2cf29d23949e7b914db4c3f2114d34f34e97a2a44a169_u256,
+            0x497d1b0bf7b0c502043fe7201a9696c466f514de3190097ef3b7d0664fc3d0bf_u256,
+            0xa43dbef675b637c554987e8a1b98be3faf8850f88fa1bdf59b124c2356135a33_u256,
+            0x4f9cf2c386b34b01d48a01ea31b5c795d1e869b42de78410b3ea1adf658f62a2_u256,
+            0x46ef4071d3ddfd9443361ef2f4b2d5da7c57eaf59785564782d0d9b95280cb9b_u256,
+            0xa48c60d6b27fd5c662d7dcd248b528474fd2598d26d51525deea3d225d7260e0_u256,
+            0x5bb6e10378329bf6e78ce3e0f3abae1fb1c4bc40e1ce1b0e1a5f5db8a7fb1897_u256
+        ];
+
+        let expected_merkle_root =
+            0xe1455aa624aa92fa8b52766199033d66e4d100b39029e69906ae594397d977af_u256;
+
         assert_eq!(merkle_root(ref txids), expected_merkle_root);
     }
 }
+

From cc290f1503857161f68e49aab051e8201580f58c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski?= <aundumla@gmail.com>
Date: Fri, 9 Aug 2024 15:48:02 +0200
Subject: [PATCH 21/23] :busts_in_silhouette: Add @olufemi-olumaiyegun as a
 contributor

---
 .all-contributorsrc | 9 +++++++++
 README.md           | 1 +
 2 files changed, 10 insertions(+)

diff --git a/.all-contributorsrc b/.all-contributorsrc
index b873cde0..194f1e24 100644
--- a/.all-contributorsrc
+++ b/.all-contributorsrc
@@ -90,6 +90,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "olufemi-olumaiyegun",
+      "name": "Olufemi Olumaiyegun",
+      "avatar_url": "https://avatars.githubusercontent.com/u/53274579?v=4",
+      "profile": "https://www.heyfemi.com/home",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,
diff --git a/README.md b/README.md
index 5c3c8408..70c9758b 100644
--- a/README.md
+++ b/README.md
@@ -139,6 +139,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
     <tr>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/harsh-ps-2003"><img src="https://avatars.githubusercontent.com/u/119954739?v=4?s=100" width="100px;" alt="Harsh Pratap Singh"/><br /><sub><b>Harsh Pratap Singh</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=harsh-ps-2003" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/Xavek"><img src="https://avatars.githubusercontent.com/u/61218841?v=4?s=100" width="100px;" alt="Xavek"/><br /><sub><b>Xavek</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=Xavek" title="Code">💻</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://www.heyfemi.com/home"><img src="https://avatars.githubusercontent.com/u/53274579?v=4?s=100" width="100px;" alt="Olufemi Olumaiyegun"/><br /><sub><b>Olufemi Olumaiyegun</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=olufemi-olumaiyegun" title="Code">💻</a></td>
     </tr>
   </tbody>
 </table>

From a43b171dd4ef048c788bc251068f6b9becd6c875 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski?= <aundumla@gmail.com>
Date: Fri, 9 Aug 2024 15:49:42 +0200
Subject: [PATCH 22/23] :busts_in_silhouette: Add @MSghais as a contributor

---
 .all-contributorsrc | 9 +++++++++
 README.md           | 1 +
 2 files changed, 10 insertions(+)

diff --git a/.all-contributorsrc b/.all-contributorsrc
index 194f1e24..6459067f 100644
--- a/.all-contributorsrc
+++ b/.all-contributorsrc
@@ -99,6 +99,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "MSghais",
+      "name": "MSG",
+      "avatar_url": "https://avatars.githubusercontent.com/u/59928086?v=4",
+      "profile": "https://github.com/MSghais",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,
diff --git a/README.md b/README.md
index 70c9758b..8feb53fe 100644
--- a/README.md
+++ b/README.md
@@ -140,6 +140,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/harsh-ps-2003"><img src="https://avatars.githubusercontent.com/u/119954739?v=4?s=100" width="100px;" alt="Harsh Pratap Singh"/><br /><sub><b>Harsh Pratap Singh</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=harsh-ps-2003" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/Xavek"><img src="https://avatars.githubusercontent.com/u/61218841?v=4?s=100" width="100px;" alt="Xavek"/><br /><sub><b>Xavek</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=Xavek" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://www.heyfemi.com/home"><img src="https://avatars.githubusercontent.com/u/53274579?v=4?s=100" width="100px;" alt="Olufemi Olumaiyegun"/><br /><sub><b>Olufemi Olumaiyegun</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=olufemi-olumaiyegun" title="Code">💻</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/MSghais"><img src="https://avatars.githubusercontent.com/u/59928086?v=4?s=100" width="100px;" alt="MSG"/><br /><sub><b>MSG</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=MSghais" title="Code">💻</a></td>
     </tr>
   </tbody>
 </table>

From 7484943c5dd04ffb6f392c7df5c96cb6fd145e34 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Maciej=20Kami=C5=84ski?= <aundumla@gmail.com>
Date: Fri, 9 Aug 2024 15:51:42 +0200
Subject: [PATCH 23/23] :busts_in_silhouette: Add @mubarak23 as a contributor

---
 .all-contributorsrc | 9 +++++++++
 README.md           | 1 +
 2 files changed, 10 insertions(+)

diff --git a/.all-contributorsrc b/.all-contributorsrc
index 6459067f..9644c0a0 100644
--- a/.all-contributorsrc
+++ b/.all-contributorsrc
@@ -108,6 +108,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "mubarak23",
+      "name": "Mubarak Muhammad Aminu",
+      "avatar_url": "https://avatars.githubusercontent.com/u/7858376?v=4",
+      "profile": "http://mubarak23.github.io/",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,
diff --git a/README.md b/README.md
index 8feb53fe..af17590c 100644
--- a/README.md
+++ b/README.md
@@ -141,6 +141,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/Xavek"><img src="https://avatars.githubusercontent.com/u/61218841?v=4?s=100" width="100px;" alt="Xavek"/><br /><sub><b>Xavek</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=Xavek" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://www.heyfemi.com/home"><img src="https://avatars.githubusercontent.com/u/53274579?v=4?s=100" width="100px;" alt="Olufemi Olumaiyegun"/><br /><sub><b>Olufemi Olumaiyegun</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=olufemi-olumaiyegun" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/MSghais"><img src="https://avatars.githubusercontent.com/u/59928086?v=4?s=100" width="100px;" alt="MSG"/><br /><sub><b>MSG</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=MSghais" title="Code">💻</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="http://mubarak23.github.io/"><img src="https://avatars.githubusercontent.com/u/7858376?v=4?s=100" width="100px;" alt="Mubarak Muhammad Aminu"/><br /><sub><b>Mubarak Muhammad Aminu</b></sub></a><br /><a href="https://github.com/keep-starknet-strange/raito/commits?author=mubarak23" title="Code">💻</a></td>
     </tr>
   </tbody>
 </table>