Added function to comput factorial of number

Algorithms.lua

@@ -1,10 +1,10 @@
 --luaClasses/Algorithms.lua
 --Matthew Ellison
 -- Created: 02-04-19
---Modified: 03-28-19
+--Modified: 06-01-21
 --This is a file of algorithms that I have found it useful to keep around at all times
 --[[
-	Copyright (C) 2019  Matthew Ellison
+	Copyright (C) 2021  Matthew Ellison
 
 	This program is free software: you can redistribute it and/or modify
 	it under the terms of the GNU Lesser General Public License as published by
@@ -353,3 +353,11 @@ function gcd(num1, num2)
 	end
 	return num1 | num2;
 end
+
+function factorial(num)
+	local fact = 1;
+	for cnt = 1, num do
+		fact = fact * cnt;
+	end
+	return fact;
+end

testAlgorithms.lua

@@ -1,7 +1,7 @@
 --lua/luaClasses/testAlgorithms.lua
 --Mathew Ellison
 -- Created: 03-28-19
---Modified: 03-12-21
+--Modified: 06-01-21
 --This script is used to test the Algorithms script
 --[[
 	Copyright (C) 2021  Matthew Ellison
@@ -340,6 +340,37 @@ local function testGCD()
 	end
 end
 
+local function testFactorial()
+	local failed = false;	--Signals whether a test was failed
+
+	--Test 1
+	local num = 1;
+	local correctAnswer = 1;
+	local answer = factorial(num);
+	if(answer ~= correctAnswer) then
+		io.write("factorial failed the first test\n");
+	end
+	--Test 2
+	local num = 10;
+	local correctAnswer = 3628800;
+	local answer = factorial(num);
+	if(answer ~= correctAnswer) then
+		io.write("factorial failed the second test\n");
+	end
+	--Test 3
+	local num = -5;
+	local correctAnswer = 1;
+	local answer = factorial(num);
+	if(answer ~= correctAnswer) then
+		io.write("factorial failed the third test\n");
+	end
+
+	--Print a message if all of the tests passed
+	if(not failed) then
+		io.write("factorial passed all tests\n");
+	end
+end
+
 
 --Create the timer to time each test
 local timer = Stopwatch:create();
@@ -409,3 +440,9 @@ timer:start();
 testGCD();
 timer:stop();
 io.write("It took " .. timer:getString() .. " to run this test\n");
+
+--Test factorial
+timer:start();
+testFactorial();
+timer:stop();
+io.write("It took " .. timer:getString() .. " to run this test\n");