Added additional test cases for ValidParenthesesTests.cs

Refactored switch-case to dictionary in ValidParentheses.cs

Author: Jccqt

Algorithms.Tests/Strings/ValidParenthesesTests.cs

@@ -7,6 +7,7 @@ namespace Algorithms.Tests.Strings
     public static class ValidParenthesesTests
     {
         [TestCase("([{}])")]
+        [TestCase("((({{{[[[]]]}}})))")]
         public static void IsValidParentheses_TrueExpected(string parentheses)
         {
             // Arrange
@@ -17,7 +18,7 @@ public static void IsValidParentheses_TrueExpected(string parentheses)
             Assert.That(isValidParentheses, Is.True);
         }
 
-        [TestCase("([)[}")]
+        [TestCase("([)[}{")]
         [TestCase("([}}])")]
         public static void IsValidParentheses_FalseExpected(string parentheses)
         {
@@ -28,5 +29,42 @@ public static void IsValidParentheses_FalseExpected(string parentheses)
             // Assert
             Assert.That(isValidParentheses, Is.False);
         }
+
+        [TestCase("(")]
+        [TestCase("(((")]
+        [TestCase("({{}")]
+        public static void IsValidParentheses_OddLength(string parentheses)
+        {
+            // Arrange
+            // Act
+            var isValidParentheses = ValidParentheses.IsValidParentheses(parentheses);
+
+            // Assert
+            Assert.That(isValidParentheses, Is.False);
+        }
+
+        [TestCase("a")]
+        [TestCase("[a]")]
+        [TestCase("//")]
+        public static void IsValidParentheses_InvalidCharFalse(string parentheses)
+        {
+            // Arrange
+            // Act
+            var isValidParentheses = ValidParentheses.IsValidParentheses(parentheses);
+
+            // Assert
+            Assert.That(isValidParentheses, Is.False);
+        }
+
+        [Test]
+        public static void IsValidParentheses_EmptyStringTrue()
+        {
+            // Arrange
+            // Act
+            var isValidParentheses = ValidParentheses.IsValidParentheses(string.Empty);
+
+            // Assert
+            Assert.That(isValidParentheses, Is.True);
+        }
     }
 }

Algorithms/Strings/ValidParentheses.cs

@@ -20,44 +20,31 @@ public static bool IsValidParentheses(string parentheses)
                 return false;
             }
 
+            Dictionary<char, char> bracketPairs = new Dictionary<char, char>
+        {
+            { ')', '(' },
+            { '}', '{' },
+            { ']', '[' },
+        };
+
             Stack<char> stack = new Stack<char>();
 
-            foreach(char c in parentheses)
+            foreach (char c in parentheses)
             {
-                switch (c)
+                if (bracketPairs.ContainsValue(c))
                 {
-                    case '(':
-                    case '{':
-                    case '[':
-                        stack.Push(c);
-                        break;
-
-                    case ')':
-                        if (stack.Count == 0 || stack.Pop() != '(')
-                        {
-                            return false;
-                        }
-
-                        break;
-
-                    case '}':
-                        if (stack.Count == 0 || stack.Pop() != '{')
-                        {
-                            return false;
-                        }
-
-                        break;
-
-                    case ']':
-                        if (stack.Count == 0 || stack.Pop() != '[')
-                        {
-                            return false;
-                        }
-
-                        break;
-
-                    default:
+                    stack.Push(c);
+                }
+                else if (bracketPairs.ContainsKey(c))
+                {
+                    if (stack.Count == 0 || stack.Pop() != bracketPairs[c])
+                    {
                         return false;
+                    }
+                }
+                else
+                {
+                    return false;
                 }
             }