C program to swap two numbers

C program to swap two numbers

C program to swap two numbers with and without using third variable, using pointers, functions (Call by reference) and using bit-wise XOR operator. Swapping means interchanging. If the program has two variables a and b where a = 4 and b = 5, after swapping them, a = 5, b = 4. In the first C program, we use a temporary variable to swap two numbers.

Swapping of two numbers in C

#include<stdio.h>

#include<conio.h>

void main()
{
  int x,y,t;

  printf("Enter two integers\n");
  scanf("%d%d",&x,&y);

  printf("Before Swapping\nFirst integer = %d\nSecond integer = %d\n", x, y);

  t = x;
  x = y;
  y = t;

  printf("After Swapping\nFirst integer = %d\nSecond integer = %d\n", x, y);

  getch();
}

Output:-

Swapping of two numbers without third variable

#include<stdio.h>

#include<conio.h>

void main()

{
   int a,b;
 
   printf("Input two integers (a & b) to swap\n");
   scanf("%d%d", &a, &b);
 
   a = a + b;
   b = a - b;
   a = a - b;

   printf("a = %d\nb = %d\n",a,b);
   getch();
}

Swap function in C language

#include <stdio.h>

#include<conio.h>

void swap(int*, int*); //Swap function declaration

void main()
{
   int x,y;

   printf("Enter the value of x and y\n");
   scanf("%d%d",&x,&y);

   printf("Before Swapping\nx = %d\ny = %d\n", x, y);

   swap(&x,&y);

   printf("After Swapping\nx = %d\ny = %d\n", x, y);

   getch();
}
//Swap function definition
void swap(int *a,int *b)
{
   int t;

   t  = *b;
   *b = *a;
   *a = t;
}

Swap two numbers using pointers

#include <stdio.h>

#include<conio.h>

void main()
{
   int x,y,*a,*b,temp;

   printf("Enter the value of x and y\n");
   scanf("%d%d",&x,&y);

   printf("Before Swapping\nx = %d\ny = %d\n", x, y);
 
   a = &x;
   b = &y;
 
   temp = *b;
   *b   = *a;
   *a   = temp;

   printf("After Swapping\nx = %d\ny = %d\n", x, y);
 
   getch();
}

C programming code to swap using bit-wise XOR

#include<stdio.h>

#include<conio.h>

void main()
{
  int x,y;

  scanf("%d%d",&x,&y);

  printf("x = %d\ny = %d\n", x, y);

  x = x ^ y;
  y = x ^ y;
  x = x ^ y;

  printf("x = %d\ny = %d\n", x, y);

  getch();

}