Question

1.) Complete the merge method below, which is the merge step of MergeSort. That is, it takes two sorted arrays as input and returns a new sorted array that contains all the elements from the two input arrays. Furthermore, it should keep all duplicated values, and it should run in O(n) time, where n is the size of the output array. public static int[] main(int[] a, int[] b) {

}

Answer 1

import java.util.Arrays;

public class MergeSortedArrays {
    public static int[] merge(int arr1[], int arr2[]){
        int len1 = arr1.length,len2 = arr2.length;
        int i = 0,j = 0,k = 0;
        int arr[] = new int[len1+len2];
        while(i<len1 && j<len2){
            if(arr1[i] <= arr2[j]){
                arr[k++] = arr1[i++];
            }
            else {
                arr[k++] = arr2[j++];
            }
        }
        while (i<len1){
            arr[k++] = arr1[i++];
        }
        while (j<len2){
            arr[k++] = arr2[j++];
        }
        return arr;
    }

    public static void main(String args[]){
        int list1[] = {1,5,8,10,18};
        Arrays.sort(list1);
        System.out.println(Arrays.toString(list1));

        int list2[] = {2,4,5,6,9,15,17,20};
        Arrays.sort(list2);
        System.out.println(Arrays.toString(list2));

        int result[] = merge(list1, list2);
        System.out.println(Arrays.toString(result));
    }
}