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C Programming Exercises

C Exercises: Swap elements using call by reference

C Pointer : Exercise-11 with Solution

Write a program in C to swap elements using call by reference.

Sample Solution:

C Code:

#include <stdio.h>
void swapNumbers(int *x,int *y,int *z);
int main()
{
    int e1,e2,e3;
	printf("\n\n Pointer : Swap elements using call by reference :\n"); 
	printf("------------------------------------------------------\n");	
    printf(" Input the value of 1st element : ");
    scanf("%d",&e1);
	printf(" Input the value of 2nd element : ");
    scanf("%d",&e2);
	printf(" Input the value of 3rd element : ");
    scanf("%d",&e3);
	
	
    printf("\n The value before swapping are :\n");
    printf(" element 1 = %d\n element 2 = %d\n element 3 = %d\n",e1,e2,e3);
    swapNumbers(&e1,&e2,&e3);
    printf("\n The value after swapping are :\n");
    printf(" element 1 = %d\n element 2 = %d\n element 3 = %d\n\n",e1,e2,e3);
    return 0;
}
void swapNumbers(int *x,int *y,int *z)
{
    int tmp;
    tmp=*y;
    *y=*x;
    *x=*z;
    *z=tmp;
}

Sample Output:

 Pointer : Swap elements using call by reference :                                                            
------------------------------------------------------                                                        
 Input the value of 1st element : 5                                                                           
 Input the value of 2nd element : 6                                                                           
 Input the value of 3rd element : 7                                                                           
                                                                                                              
 The value before swapping are :                                                                              
 element 1 = 5                                                                                                
 element 2 = 6                                                                                                
 element 3 = 7                                                                                                
                                                                                                              
 The value after swapping are :                                                                               
 element 1 = 7                                                                                                
 element 2 = 5                                                                                                
 element 3 = 6

Flowchart:

Flowchart: Swap elements using call by reference

C Programming Code Editor:

#include <stdio.h>
void swapNumbers(int *x,int *y,int *z);
int main()
{
    int e1,e2,e3;
	printf("\n\n Pointer : Swap elements using call by reference :\n"); 
	printf("------------------------------------------------------\n");	
    printf(" Input the value of 1st element : ");
    scanf("%d",&e1);
	printf(" Input the value of 2nd element : ");
    scanf("%d",&e2);
	printf(" Input the value of 3rd element : ");
    scanf("%d",&e3);
	
	
    printf("\n The value before swapping are :\n");
    printf(" element 1 = %d\n element 2 = %d\n element 3 = %d\n",e1,e2,e3);
    swapNumbers(&e1,&e2,&e3);
    printf("\n The value after swapping are :\n");
    printf(" element 1 = %d\n element 2 = %d\n element 3 = %d\n\n",e1,e2,e3);
    return 0;
}
void swapNumbers(int *x,int *y,int *z)
{
    int tmp;
    tmp=*y;
    *y=*x;
    *x=*z;
    *z=tmp;
}

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