Difference Between Call By Value And Call By Reference

 Call By Value And Call By Reference:-

1- Call By Value-:

•  In call by value each of the actual arguement in the calling function is copied to the formal arguement.
• The change made in the formal arguement have no effect on the values of actual arguement in calling function.

2- Call By Reference-:

•  In call by reference the address of actual arguement in the calling function is copied to the formal arguement.
• The change made in the formal arguement, made change on the values of actual arguement in calling function.

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Example-:

#include<stdio.h>

#include<conio.h>

main()

{int x=0,y=0,res=0;

printf("Enter the value of x and y:-");

scanf("%d %d ",&x,&y);

printf("\n x=%d,y=%d"x,y);

res= swap_value(intx,inty)

printf("\n Now x=%d y=%d"x,y);

getch();

}

int swap_value(intx,inty)

{int t=0;

printf("\n here x=%d y=%d",x,y);

t=x;

x=y;

y=t;

printf("\n now x=%d t=%d y=%d",x,t,y);

}

Output-:

Enter the value of x and y:-10

20

x=10 y=20

here x=10 y=20

now x=20 t=10 y=10

now x=10 y=20