Create Merge_Sort.java

Merge_Sort.java

@@ -0,0 +1,47 @@
+import java.util.*;
+
+public class MergeSort {
+  public static void main(String[] args) {
+    Scanner sc = new Scanner(System.in);
+    System.out.println("Enter the size of the Array: ");
+    int size_of_arry = sc.nextInt(); // size of array, to b entered by the user
+    int arr[] = new int[size_of_arry];
+    System.out.println("Enter Array Elements ");
+    for (int i = 0; i < size_of_arry; i++)
+      arr[i] = sc.nextInt(); // element of array, to be entered by the user
+    arr = Merge_sort(arr, size_of_arry);
+    System.out.println("Array after Merge Sort is: ");
+    for (int i = 0; i < size_of_arry; i++)
+      System.out.print(arr[i] + " ");
+    System.out.println("\n");
+  }
+
+  static int[] Merge_sort(int arr[], int size) {
+    if (size > 1) {
+      int mid = size / 2;
+      int[] first = Arrays.copyOfRange(arr, 0, mid);
+      first = Merge_sort(first, mid); // recursive call for first half array
+      int[] second = Arrays.copyOfRange(arr, mid, size);
+      second = Merge_sort(second, size - mid); // recursive call for second half array
+      arr = Merge_arrays(first, second, mid, size - mid);
+    }
+    return arr;
+  }
+
+  static int[] Merge_arrays(int first[], int second[], int n, int m) // respectively
+  {
+    int arr[] = new int[n + m];
+    int i = 0, f = 0, s = 0;
+    while (f < n && s < m) {
+      if (first[f] < second[s])
+        arr[i++] = first[f++];
+      else
+        arr[i++] = second[s++];
+    }
+    while (f < n)
+      arr[i++] = first[f++];
+    while (s < m)
+      arr[i++] = second[s++];
+    return arr;
+  }
+}