Create MetaBinarySearchTest.java

Author: Fenirok

src/test/java/com/thealgorithms/searches/MetaBinarySearchTest.java

@@ -0,0 +1,93 @@
+package com.thealgorithms.searches;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import org.junit.jupiter.api.Test;
+
+class MetaBinarySearchTest {
+
+    private final MetaBinarySearch metaBinarySearch = new MetaBinarySearch();
+
+    @Test
+    void testTargetFound() {
+        int[] sortedArray = { 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21 };
+        int target = 13;
+        int expectedIndex = 6; // 13 is at index 6
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testTargetNotFound() {
+        int[] sortedArray = { 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21 };
+        int target = 14; // 14 is not in the array
+        int expectedIndex = -1;
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testEmptyArray() {
+        int[] sortedArray = {};
+        int target = 5;
+        int expectedIndex = -1;
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testSingleElementArrayFound() {
+        int[] sortedArray = { 10 };
+        int target = 10;
+        int expectedIndex = 0;
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testSingleElementArrayNotFound() {
+        int[] sortedArray = { 10 };
+        int target = 5;
+        int expectedIndex = -1;
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testTargetAtStart() {
+        int[] sortedArray = { 2, 4, 6, 8, 10 };
+        int target = 2;
+        int expectedIndex = 0; // 2 is at the start
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testTargetAtEnd() {
+        int[] sortedArray = { 2, 4, 6, 8, 10 };
+        int target = 10;
+        int expectedIndex = 4; // 10 is at the end
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testArrayWithNegativeNumbers() {
+        int[] sortedArray = { -10, -5, 0, 5, 10, 15 };
+        int target = 5;
+        int expectedIndex = 3;
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testArrayWithAllNegativeNumbers() {
+        int[] sortedArray = { -20, -15, -10, -5, -1 };
+        int target = -10;
+        int expectedIndex = 2;
+        assertEquals(expectedIndex, metaBinarySearch.metaBinarySearch(sortedArray, target));
+    }
+
+    @Test
+    void testArrayWithDuplicates() {
+        int[] sortedArray = { 1, 3, 5, 5, 5, 7, 9 };
+        int target = 5;
+        // Meta Binary Search can return any index where 5 is found (2, 3, or 4).
+        int actualIndex = metaBinarySearch.metaBinarySearch(sortedArray, target);
+        // Assert that the index is valid (any occurrence of 5)
+        boolean isValidIndex = actualIndex == 2 || actualIndex == 3 || actualIndex == 4;
+        assertEquals(true, isValidIndex, "The index should be any occurrence of 5 (2, 3, or 4).");
+    }
+
+}