Merge Sort in java (#540)

Programming/Java/MergeSort/MergeSort.java

@@ -0,0 +1,53 @@
+package Programming.Java.MergeSort;
+
+public class MergeSort {
+
+  public static void merge(int[] arr, int l, int mid, int r) {
+    int[] b = new int[arr.length];
+    int i = l;
+    int j = mid + 1;
+    int k = l;
+    while (i <= mid && j <= r) {
+      if (arr[i] < arr[j]) {
+        b[k] = arr[i];
+        i++;
+      } else {
+        b[k] = arr[j];
+        j++;
+      }
+      k++;
+    }
+    if (i > mid) {
+      while (j <= r) {
+        b[k] = arr[j];
+        k++;
+        j++;
+      }
+    } else {
+      while (i <= mid) {
+        b[k] = arr[i];
+        k++;
+        i++;
+      }
+    }
+    for (k = l; k <= r; k++) {
+      arr[k] = b[k];
+    }
+  }
+
+  public static void mergeSort(int[] arr, int l, int r) {
+    if (l < r) {
+      int mid = (l + r) / 2;
+      mergeSort(arr, l, mid);
+      mergeSort(arr, mid + 1, r);
+      merge(arr, l, mid, r);
+    }
+  }
+
+  public static void main(String[] args) {
+    int[] arr = { 73, 188, 894, 915, 940, 616, 900, 548 };
+    mergeSort(arr, 0, arr.length - 1);
+    for (int j : arr)
+      System.out.print(j + " ");
+  }
+}