Add BinarySearchTest for both implementations

Author: junnengsoo

out/production/src/src/dataStructures/disjointSet/quickFind/quick_find.iml

@@ -31,7 +31,7 @@ public class BinarySearchTemplated {
      */
     // The condition should be changed accordingly
     public static boolean condition(int value, int target) {
-        return value < target;
+        return value >= target;
     }
 
     /**
@@ -47,9 +47,9 @@ public static int search(int[] arr, int target) {
         int low = 0;
         while (low < high) {
             int mid = low + (high - low) / 2; // equivalent to high + low / 2 but reduces cases of integer overflow
-            if (condition(arr[mid], target)) { // if value < target
+            if (condition(arr[mid], target)) { // if value >= target
                 high = mid;
-            } else { // if value >= target
+            } else { // if value < target
                 low = mid + 1;
             }
         }

src/algorithms/searches/binarySearch/BinarySearchTemplated.java

@@ -33,8 +33,8 @@ This template will work for most binary search problems and will only require th
 Simply modify the initialisation of the high and low pointer according to the search space.
 
 ### Condition (Requires change)
-We assume that when the condition returns true, the current value "fails" and when the condition returns false, the 
-current value "passes".
+We assume that when the condition returns true, the current value "passes" and when the condition returns false, the 
+current value "fails".
 
 In this template, we want to find the first "pass" in the array.
 

src/algorithms/searches/binarySearch/README.md

@@ -1,4 +1,51 @@
 package test.algorithms.binarySearchTest;
 
+import org.junit.Test;
+
+import src.algorithms.searches.binarySearch.BinarySearchTemplated;
+import src.algorithms.searches.binarySearch.BinarySearch;
+
+import java.util.Arrays;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+
 public class BinarySearchTest {
+    @Test
+    public void test_binarySearch() {
+        // Test 1: even number of elements
+        int[] firstArray = {1, 5, 10, 12};
+        int firstResult = BinarySearch.search(firstArray, 1);
+
+        // Test 2: odd number of elements
+        int[] secondArray = {1, 5, 10, 11, 12};
+        int secondResult = BinarySearch.search(secondArray, 11);
+
+        // Test 3: target not in array
+        int[] thirdArray = {1, 5, 10, 11, 12};
+        int thirdResult = BinarySearch.search(thirdArray, 3);
+
+        assertEquals(0, firstResult);
+        assertEquals(3, secondResult);
+        assertEquals(-1, thirdResult);
+    }
+
+    @Test
+    public void test_binarySearchTemplated() {
+        // Test 1: even number of elements
+        int[] firstArray = {1, 5, 10, 12};
+        int firstResult = BinarySearchTemplated.search(firstArray, 1);
+
+        // Test 2: odd number of elements
+        int[] secondArray = {1, 5, 10, 11, 12};
+        int secondResult = BinarySearchTemplated.search(secondArray, 11);
+
+        // Test 3: target not in array
+        int[] thirdArray = {1, 5, 10, 11, 12};
+        int thirdResult = BinarySearchTemplated.search(thirdArray, 3);
+
+        assertEquals(0, firstResult);
+        assertEquals(3, secondResult);
+        assertEquals(-1, thirdResult);
+    }
 }