
II-222 Programming Concepts
26. Explain call by value and call by address with programming example of each one.
Ans: When value is passed in a function, it is known as call by value. Value is changed only inside
the function. The changed value is not reflected in the original value.
For example,
#include<stdio.h>
#include<conio.h>
void swap(int,int);
void main()
{
int a,b;
clrscr();
printf("enter two integer number\n");
scanf("%d%d",&a,&b);
printf(" before calling swap function \n");
printf("a=%d\t b=%d\n",a,b);
swap(a,b);
printf("after calling swap function");
printf("a=%d\tb=%d\n",a,b);
getch( );
}
void swap(int p,int q)
{
int t;
t=p;
p=q;
q=t;
}
Call by reference: ...