[Hacker Rank] Interview Preparation Kit: Array: 2D Array - DS. Better test cases.

Author: Gonzalo Diaz

src/algorithm_exercises_csharp/hackerrank/interview_preparation_kit/arrays/TwoDArray.cs

@@ -31,12 +31,7 @@ private static List<int> getHourGlass(List<List<int>> arr, int positionX, int po
 
   public static int hourglassSum(List<List<int>> arr)
   {
-    int matrixSize = 0;
-
-    if (arr.Count > 0)
-    {
-      matrixSize = arr.Count;
-    }
+    int matrixSize = arr.Count;
 
     int matrixStartIndex = 1;
     int matrixEndIndex = matrixSize - 2;

src/algorithm_exercises_csharp_test/Resources/hackerrank/interview_preparation_kit/arrays/2d_array.testcases.json

@@ -10,5 +10,29 @@
       [0, 0, 1, 2, 4, 0]
     ],
     "expected": 19
+  },
+  {
+    "title": "Sample Test Case 1",
+    "input": [
+      [1, 1, 1, 0, 0, 0],
+      [0, 1, 0, 0, 0, 0],
+      [1, 1, 1, 0, 0, 0],
+      [0, 9, 2, -4, -4, 0],
+      [0, 0, 0, -2, 0, 0],
+      [0, 0, -1, -2, -4, 0]
+    ],
+    "expected": 13
+  },
+  {
+    "title": "Sample Test Case 2",
+    "input": [
+      [-9, -9, -9, 1, 1, 1],
+      [0, -9, 0, 4, 3, 2],
+      [-9, -9, -9, 1, 2, 3],
+      [0, 0, 8, 6, 6, 0],
+      [0, 0, 0, -2, 0, 0],
+      [0, 0, 1, 2, 4, 0]
+    ],
+    "expected": 28
   }
 ]

src/algorithm_exercises_csharp_test/hackerrank/interview_preparation_kit/arrays/TwoDArray.Test.cs

@@ -33,5 +33,16 @@ public void testHourglassSum()
       Assert.AreEqual(test.expected, result);
     }
   }
+
+
+  [TestMethod]
+  public void testHourglassSumEdgeCases()
+  {
+    List<List<int>> input = [];
+    int expected = 0;
+    int result = TwoDArray.hourglassSum(input);
+
+    Assert.AreEqual(expected, result);
+  }
 }