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C program to merge two arrays in third array which is creating dynamically

In this C program, we are merging two one dimensional array in third array, where size of first and second arrays are different and the size of third array will be size of first array + second array.
Submitted by IncludeHelp, on April 14, 2018

Problem statement

Given two dimensional array and we have to merge them in a single array using C program.

Example

First array elements: 10, 20 ,30
Second array elements: 40, 50, 60

Output:
Third array: 10, 20, 30, 40, 50, 60

Program to merge two arrays in C

/** C program to merge two arrays into a new
 * array
*/

#include <stdio.h>
#include <stdlib.h>
int main()
{
    // declare two int arrays
    int array_1[30] = {0};
    int array_2[30] = {0};
    
    // declare an int pointer which
    // will store the combination of 
    // array_1 and array_2
    int *c;
    
    // declare some local variables
    int i=0 , j=0 , k=0;

    // x will store the number of elements for array_1
    // y will store the number of elements for array_2
    // z will store the total number of elements of array_2 array_1
    int x=0 , y=0 , z=0;

    printf("\nEnter the number of elements for both arrays..");
    printf("\nFor array_1 : ");
    scanf("%d",&x);
    printf("\nFor array_2 : ");
    scanf("%d",&y);
 
    printf("\nEnter the elements for array_1..\n");
    for(i=0 ; i<x ; i++)
    {
        printf("array_1[%d] : ",i);
        scanf("%d",&array_1[i]);
    }
    
    printf("\nEnter the elements for array_2..\n");
    for(i=0 ; i<x ; i++)
    {
        printf("array_2[%d] : ",i);
        scanf("%d",&array_2[i]);
    }
    
    // Calculate the total elements for pointer "c"
    z = x +y;
    
    printf("\nTotal elements are : %d\n",z);
    
    // now allocate dynamic memory to pointer "c"
    // but according to the "z"
    c = (int*)malloc(z * sizeof(int));
    
    for(i=0,j=0,k=0 ; i<z,j<x,k<y ; i++)
    {
        c[i] = array_1[j++];
        if(i>=x)
        {
            c[i] = array_2[k++];
        }
    }
    
    printf("\nThe final array after merging the two arrays is..");
    for(i=0;i<z;i++)
    {
        printf("\nC[%d] : %d",i,c[i]);
    }
    
    return 0;
}

Output

Enter the number of elements for both arrays..   
For array_1 : 3  
 
For array_2 : 3  
 
Enter the elements for array_1.. 
array_1[0] : 10  
array_1[1] : 20  
array_1[2] : 30  
 
Enter the elements for array_2.. 
array_2[0] : 40  
array_2[1] : 50  
array_2[2] : 60  
 
Total elements are : 6
   
The final array after merging the two arrays is..
C[0] : 10
C[1] : 20
C[2] : 30
C[3] : 40
C[4] : 50
C[5] : 60

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