Refactoring.

LeetCode/src/LeetCode.Challenges/CoinChange/Description.md

@@ -1,6 +1,7 @@
 # Coin Change
 
-You are given an integer array coins representing coins of different denominations and an integer amount representing a total amount of money.  
+You are given an integer array `coins` representing coins of different denominations 
+and an integer `amount` representing a total amount of money.  
 Return the fewest number of coins that you need to make up that amount.  
 If that amount of money cannot be made up by any combination of the coins, return -1.
 

LeetCode/src/LeetCode.Challenges/CoinChange/SolutionV1.cs

@@ -1,11 +1,13 @@
 namespace LeetCode.Challenges.CoinChange;
 
-public class SolutionV1
+public static class SolutionV1
 {
-    public int CoinChange(int[] coins, int amount)
+    public static int CoinChange(int[] coins, int amount)
     {
         var cache = new Dictionary<int, int>();
 
+        return GetChange(amount);
+
         int GetChange(int tempAmount)
         {
             if (tempAmount == 0)
@@ -36,7 +38,5 @@ int GetChange(int tempAmount)
             cache[tempAmount] = minCoins != int.MaxValue ? minCoins : -1;
             return cache[tempAmount];
         }
-
-        return GetChange(amount);
     }
 }

LeetCode/tests/LeetCode.Challenges.UnitTests/CoinChange/SolutionV1Tests.cs

@@ -0,0 +1,37 @@
+using LeetCode.Challenges.CoinChange;
+using Xunit;
+using Shouldly;
+
+namespace LeetCode.Challenges.UnitTests.CoinChange;
+
+public class SolutionV1Tests
+{
+    [Theory]
+    [MemberData(nameof(CoinChangeTestCases))]
+    public void GivenCoins_WhenCoinChange_ThenResultAsExpected(int[] coins, int amount, int expected)
+    {
+        SolutionV1.CoinChange(coins, amount).ShouldBe(expected);
+    }
+
+    public static IEnumerable<object[]> CoinChangeTestCases()
+    {
+        yield return [new[] { 1, 2, 5 }, 11, 3];
+        yield return [new[] { 2 }, 3, -1];
+        yield return [new[] { 1 }, 0, 0];
+        yield return [new[] { 186, 419, 83, 408 }, 6249, 20];
+        yield return [new[] { 1, 3, 4 }, 6, 2];
+        yield return [new[] { 5 }, 5, 1];
+        yield return [new[] { 5 }, 0, 0];
+        yield return [new[] { 5 }, 2, -1];
+        yield return [new[] { 2, 5, 10 }, 1, -1];
+        yield return [new[] { 10, 5 }, 20, 2];
+        yield return [new[] { 1, 5, 10, 25 }, 30, 2];
+        yield return [new[] { 2, 3 }, 7, 3];
+        yield return [new[] { 1, 2, 5 }, 100, 20];
+        yield return [new[] { 7, 3, 2 }, 8, 3];
+        yield return [new[] { 1, 7, 10 }, 14, 2];
+        yield return [new[] { 1, 3, 4, 7 }, 15, 3];
+        yield return [new[] { 25, 50, 100 }, 30, -1];
+        yield return [new[] { 9, 6, 5, 1 }, 11, 2];
+    }
+}