Question

Use C programming

Swap two arrays using pointers

Given two integer arrays, swap the two arrays using pointers.

Input:

    4

    1 2 3 4

    5

    4 5 6 7 8

    where:

• First line represents the number of elements in the first array.
• Second line represents the elements in the first array.
• Third line represents the number of elements in the second array.
• Fourth line represents the elements in the second array.

Output:

    4 5 6 7 8

    1 2 3 4

Answer 1

#include <stdio.h>
#include <stdlib.h>

int main(void) {
        int s1, s2;
        int i;

        scanf("%d", &s1);
        int *arr1 = malloc(sizeof(int) * s1);
        for(i=0; i<s1; i++) {
                scanf("%d", &arr1[i]);                
        }

        scanf("%d", &s2);
        int *arr2 = malloc(sizeof(int) * s2);
        for(i=0; i<s2; i++) {
                scanf("%d", &arr2[i]);                
        }

        // now both arrays are read in arr1 and arr2.
        // now swap pointers.
        int *temp = arr1;
        arr1 = arr2;
        arr2 = temp;

        // print
        for(i=0; i<s2; i++) {
                printf("%d ", arr1[i]);                
        }
        printf("\n");
        for(i=0; i<s1; i++) {
                printf("%d ", arr2[i]);                
        }
        printf("\n");


        return 0;
}

Please upvote, as i have given the exact answer as asked in question. Still in case of any issues in code, let me know in comments. Thanks!