improved vigenere encoder coverage (#107)

* improved vigenere encoder coverage

* removed commented code

Author: 1fisedi

Algorithms.Tests/Encoders/VigenereEncoderTests.cs

@@ -14,7 +14,7 @@ public void DecodedStringIsTheSame()
             var random = new Randomizer();
             var encoder = new VigenereEncoder();
             var message = random.GetString();
-            var key = random.GetString();
+            var key = random.GetString(random.Next(0,1000));
 
             // Act
             var encoded = encoder.Encode(message, key);

Algorithms.Tests/Knapsack/NaiveKnapsackSolverTests.cs

@@ -7,15 +7,15 @@ namespace Algorithms.Tests.Knapsack
     public class NaiveKnapsackSolverTests
     {
         [Test]
-        public void TakesHalf([Random(0, 1000, 100)]int length)
+        public void TakesHalf([Random(0, 1000, 100,Distinct = true)]int length)
         {
             //Arrange
             var solver = new NaiveKnapsackSolver<int>();
             var items = Enumerable.Repeat(42, 2 * length).ToArray();
             var expectedResult = Enumerable.Repeat(42, length);
 
             //Act
-            var result = solver.Solve(items, length, x => 1, x => 1);
+            var result = solver.Solve(items, length, x => 1, y => 1);
 
             //Assert
             Assert.AreEqual(expectedResult, result);

Algorithms.Tests/Numeric/GaussJordanEliminationTests.cs

@@ -14,7 +14,7 @@ public static void NonSquaredMatrixThrowsException()
         {
             // Arrange
             var solver = new GaussJordanElimination();
-            var input = new double[,] { { 2, 4, 5 }, { 9, 2, 1 }, { 3, 17, 7 } };
+            var input = new double[,] { { 2, -1, 5 }, { 0, 2, 1 }, { 3, 17, 7 } };
 
             // Act
             void Act() => solver.Solve(input);