Merge two sorted arrays in Java

Merge two sorted arrays Java 

Merge two sorted arrays in java.
Lets simplify problem statement, given two sorted arrays, you need to merge it in one array such that merged array should also be sorted. 
Lets understand the problem statement graphically and it will be more clear,


Take 3 pointers,
  1. Pointer 1 pointing to 1st index of Array 1
  2. Pointer 2 pointing to 1st index of Array 2
  3. Pointer 3 pointing to 1st index of Output Array.
  1. Compare data of Array 1 and Array 2, whichever is smaller, copy that to Output array.
  2. Increment Pointer of Output array and Pointer of Array in which data was smaller. 
  3. If data in Array 1 and Array 2 is same, then copy data from Array 1 and Array 2 to Output array and increment pointer of all 3 Arrays.
We can follow above procedure until length of Array 1 and and Array 2 is same.
If one of the Array is smaller then repeat above procedure until length of smaller Array.
Copy the remaining element of larger array to Output array.

Merge two sorted arrays Java Program

public class Merge2SortedArrayInOne {

 public static void main(String[] args) {
  int[] mergedArr = mergeTwoSortedArray(new int[]{10,15,22,80}, new int[]{5,8,11,15,70,90});
  for (int i : mergedArr) {
   System.out.print(i + " ");

 public static int[] mergeTwoSortedArray(int[] arr1, int[] arr2) {
  int[] mergedArray = new int[arr1.length + arr2.length];
  int i = 0, j = 0, index = 0;

  while (i < arr1.length && j < arr2.length){
   if (arr1[i] < arr2[j])       
    mergedArray[index++] = arr1[i++];
    mergedArray[index++] = arr2[j++];               

  while (i < arr1.length)  
   mergedArray[index++] = arr1[i++];

  while (j < arr2.length)    
   mergedArray[index++] = arr2[j++];

  return mergedArray;

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Enjoy !!!! 

If you find any issue in post or face any error while implementing, Please comment.

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