2
3
4
5
3
4
Sum=21
C Programming Pointers and Functions - Call by Reference
When, argument is passed using pointer, address of the memory location is passed instead of value.
Example of Pointer And Functions
Program to swap two number using call by reference.
/* C Program to swap two numbers using pointers and function. */
#include <stdio.h>
void swap(int *a,int *b);
int main(){
int num1=5,num2=10;
swap(&num1,&num2); /* address of num1 and num2 is passed to swap function */
printf("Number1 = %d\n",num1);
printf("Number2 = %d",num2);
return 0;
}
void swap(int *a,int *b){ /* pointer a and b points to address of num1 and num2
respectively */
int temp;
temp=*a;
*a=*b;
*b=temp;
}