Merge pull request #8240 from vimde/master

BAEL-3399: How to merge two sorted arrays into a sorted array

algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/mergesortedarrays/SortedArrays.java

@@ -0,0 +1,33 @@
+package com.baeldung.algorithms.mergesortedarrays;
+
+public class SortedArrays {
+
+    public static int[] merge(int[] foo, int[] bar) {
+
+        int fooLength = foo.length;
+        int barLength = bar.length;
+
+        int[] merged = new int[fooLength + barLength];
+
+        int fooPosition, barPosition, mergedPosition;
+        fooPosition = barPosition = mergedPosition = 0;
+
+        while (fooPosition < fooLength && barPosition < barLength) {
+            if (foo[fooPosition] < bar[barPosition]) {
+                merged[mergedPosition++] = foo[fooPosition++];
+            } else {
+                merged[mergedPosition++] = bar[barPosition++];
+            }
+        }
+
+        while (fooPosition < fooLength) {
+            merged[mergedPosition++] = foo[fooPosition++];
+        }
+
+        while (barPosition < barLength) {
+            merged[mergedPosition++] = bar[barPosition++];
+        }
+
+        return merged;
+    }
+}

algorithms-miscellaneous-5/src/test/java/com/baeldung/algorithms/mergesortedarrays/SortedArraysUnitTest.java

@@ -0,0 +1,29 @@
+package com.baeldung.algorithms.mergesortedarrays;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import org.junit.jupiter.api.Test;
+
+import com.baeldung.algorithms.mergesortedarrays.SortedArrays;
+
+public class SortedArraysUnitTest {
+
+    @Test
+    public void givenTwoSortedArrays_whenMerged_thenReturnMergedSortedArray() {
+
+        int[] foo = { 3, 7 };
+        int[] bar = { 4, 8, 11 };
+        int[] merged = { 3, 4, 7, 8, 11 };
+
+        assertArrayEquals(merged, SortedArrays.merge(foo, bar));
+    }
+
+    @Test
+    public void givenTwoSortedArraysWithDuplicates_whenMerged_thenReturnMergedSortedArray() {
+
+        int[] foo = { 3, 3, 7 };
+        int[] bar = { 4, 8, 8, 11 };
+        int[] merged = { 3, 3, 4, 7, 8, 8, 11 };
+
+        assertArrayEquals(merged, SortedArrays.merge(foo, bar));
+    }
+}