From 94142e3a2de7aa3770f48d528ee763e2ab9149ea Mon Sep 17 00:00:00 2001
From: Victor Payno <vpayno@users.noreply.github.com>
Date: Mon, 15 Apr 2024 21:36:25 -0700
Subject: [PATCH] tcl/difference-of-squares: 1st iteration

---
 tcl/README.md                                 |  1 +
 tcl/difference-of-squares/README.md           |  7 +-
 .../difference-of-squares.tcl                 | 15 ++--
 tcl/difference-of-squares/run-tests-tcl.txt   | 68 +++++++++++++++++++
 4 files changed, 84 insertions(+), 7 deletions(-)
 create mode 100644 tcl/difference-of-squares/run-tests-tcl.txt

diff --git a/tcl/README.md b/tcl/README.md
index c15fb72b..53de4825 100644
--- a/tcl/README.md
+++ b/tcl/README.md
@@ -25,3 +25,4 @@
 - [reverse-string](./reverse-string/README.md)
 - [roman-numerals](./roman-numerals/README.md)
 - [scrabble-score](./scrabble-score/README.md)
+- [difference-of-squares](./difference-of-squares/README.md)
diff --git a/tcl/difference-of-squares/README.md b/tcl/difference-of-squares/README.md
index 12c9d87c..62cdbc9d 100644
--- a/tcl/difference-of-squares/README.md
+++ b/tcl/difference-of-squares/README.md
@@ -30,4 +30,9 @@ Finding the best algorithm for the problem is a key skill in software engineerin
 
 ### Based on
 
-Problem 6 at Project Euler - https://projecteuler.net/problem=6
\ No newline at end of file
+Problem 6 at Project Euler - https://projecteuler.net/problem=6
+
+### My Solution
+
+- [difference-of-squares.tcl](./difference-of-squares.tcl)
+- [run-tests](./run-tests-tcl.txt)
diff --git a/tcl/difference-of-squares/difference-of-squares.tcl b/tcl/difference-of-squares/difference-of-squares.tcl
index 6986a715..5d26ffd1 100644
--- a/tcl/difference-of-squares/difference-of-squares.tcl
+++ b/tcl/difference-of-squares/difference-of-squares.tcl
@@ -1,11 +1,14 @@
-proc squareOfSum {n} {
-    throw {NOT_IMPLEMENTED} "Implement this procedure."
+proc squareOfSum {number} {
+    return [expr ($number * ($number + 1) / 2) ** 2]
 }
 
-proc sumOfSquares {n} {
-    throw {NOT_IMPLEMENTED} "Implement this procedure."
+proc sumOfSquares {number} {
+    return [expr ($number * ($number + 1) * (2 * $number + 1) / 6)]
 }
 
-proc differenceOfSquares {n} {
-    throw {NOT_IMPLEMENTED} "Implement this procedure."
+proc differenceOfSquares {number} {
+    set square [squareOfSum $number]
+    set sum [sumOfSquares $number]
+
+    return [expr {$square - $sum}]
 }
diff --git a/tcl/difference-of-squares/run-tests-tcl.txt b/tcl/difference-of-squares/run-tests-tcl.txt
new file mode 100644
index 00000000..8e757f19
--- /dev/null
+++ b/tcl/difference-of-squares/run-tests-tcl.txt
@@ -0,0 +1,68 @@
+Running automated test file(s):
+
+
+===============================================================================
+
+Running: ttclcheck -scan /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares
+ttclcheck version: 0.18 Copyright 2013 Artur Trzewik
+All Rights Reserved.
+
+GPL licensed software
+warn: pass shallow
+warn: parsing /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl
+warn: parsing /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl
+warn: pass collect
+warn: parsing /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl
+warn: parsing /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl
+warn: pass report
+warn: parsing /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl: parsing file /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl:17: unknown variable ::tcltest::numTests <<$::tcltest::numTests>>
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/testHelpers.tcl: errors file: 1
+warn: parsing /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl: parsing file /home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl:2: possible unintended double substitution for expr use {} <<($number>>
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl:6: possible unintended double substitution for expr use {} <<($number>>
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl:13: expect variable 'square' as 'numeric' but is 'string {}' <<$square>>
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl:13: expect variable 'sum' as 'numeric' but is 'string {}' <<$sum>>
+/home/vpayno/git_vpayno/exercism-workspace/tcl/difference-of-squares/difference-of-squares.tcl: errors file: 4
+errors all: 5 (13.89% lines)
+lines: 36 in: 00:00:00 59 lines/sec: 610.17
+commands: 5 variables: 1
+signature params 9 unknown: 5 55.56% unknown variables 0.00%
+
+real	0m0.127s
+user	0m0.103s
+sys	0m0.025s
+
+===============================================================================
+
+Running: nagelfar -s _ ./difference-of-squares.tcl
+Checking file ./difference-of-squares.tcl
+Line   2: W Expr without braces
+Line   6: W Expr without braces
+
+real	0m0.034s
+user	0m0.026s
+sys	0m0.007s
+
+===============================================================================
+
+Running: RUN_ALL=1 tclsh ./difference-of-squares.test
+difference-of-squares.test:	Total	9	Passed	9	Skipped	0	Failed	0
+
+real	0m0.010s
+user	0m0.008s
+sys	0m0.002s
+
+
+===============================================================================
+
+Running: misspell .
+
+real	0m0.019s
+user	0m0.023s
+sys	0m0.008s
+
+===============================================================================
+