Program to swap two numbers using functions. #include#include void main() { void swap(int,int); int a,b,r; clrscr(); printf(“enter value for a&b: ”); scanf(“%d%d”,&a,&b); swap(a,b); getch(); } void swap(int a,int b) { int temp; temp=a; a=b; b=temp; printf(“after swapping the value for a & b is : %d %d”,a,b); } Output: enter value for a&b: 4 5 after swapping the value for a & b : 5 4