From 37dcfa81919c353864cbcc1a7e5d0d36963bd381 Mon Sep 17 00:00:00 2001
From: Rishabh Gupta <52212344+rishabh217@users.noreply.github.com>
Date: Sat, 16 Oct 2021 12:00:30 +0530
Subject: [PATCH] Added GrayCode.java

---
 Programming_Languages/Java/GrayCode.java | 35 ++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 Programming_Languages/Java/GrayCode.java

diff --git a/Programming_Languages/Java/GrayCode.java b/Programming_Languages/Java/GrayCode.java
new file mode 100644
index 0000000..1261cad
--- /dev/null
+++ b/Programming_Languages/Java/GrayCode.java
@@ -0,0 +1,35 @@
+import java.util.*;
+
+public class GrayCode {
+
+  public static List  grayCode(int n) {
+    List< Integer> ans = new ArrayList< >();
+    if (n == 0) {
+      ans.add(0);
+      return ans;
+    }
+    backtrack(ans, n);
+    return ans;
+  }
+
+  static int temp;
+
+  private static void backtrack(List ans, int n) {
+    if (n == 0) {
+      ans.add(temp);
+      return;
+    }
+
+    backtrack(ans, n - 1);
+
+    temp = temp ^ (1 << (n - 1));
+    backtrack(ans, n - 1);
+  } 
+  
+  public static void main(String[] args) {
+    Scanner scn = new Scanner(System.in);
+    List ans = grayCode(scn.nextInt());
+    Collections.sort(ans);
+    System.out.println(ans);
+  }
+}
\ No newline at end of file