C Programs to Swap Two Numbers

C program to swap two numbers with and without using third variable, swapping in c using function. swapping means interchanging

Program to Swap Numbers Using Temporary Variable:

#include<stdio.h>
main()
{
    int x,y,temp;
    printf("Enter the value of x:");
    scanf("%d",&x);
    printf("Enter the value of y:");
    scanf("%d",&y);
    temp=x;
    x=y;
    y=temp;
    printf("The value of x: %d\n",x);
    printf("The value of y: %d",y);
} 

Output:

We can swap two numbers without using third variable. There are two common ways to swap two numbers without using third variable

Program to Swap Number Without Using Temporary Variables:

1.using '+' and '-' Arthmetic Operators

#include<stdio.h>
main()
{
    int x,y;
    printf("Enter the value of x:");
    scanf("%d",&x);
    printf("Enter the value of y:");
    scanf("%d",&y);
    x=x+y;
    y=x-y;
    x=x-y;
    printf("The value of x: %d\n",x);
    printf("The value of y: %d",y);
}

Output:

2..using * and '/' Arthmetic Operators

#include<stdio.h>
main()
{
    int x,y;
    printf("Enter the value of x:");
    scanf("%d",&x);
    printf("Enter the value of y:");
    scanf("%d",&y);
    x=x*y;
    y=x/y;
    x=x/y;
    printf("The value of x: %d\n",x);
    printf("The value of y: %d",y);
}

Output:

It would be good if we use a function to swap the given numbers instead of writing the entire logic in the main function: 

#include<stdio.h>
void swap(int &,int &);
main()
{
    int x,y;
    printf("Enter the value of x:");
    scanf("%d",&x);
    printf("Enter the value of y:");
    scanf("%d",&y);
    swap(x,y);
    printf("The value of x: %d",x);
    printf("\nThe value of y: %d",y);
}
void swap(int &x,int &y)
{
    x=x+y;
    y=x-y;
    x=x-y;
}

Output: