C Program for Swapping Two Numbers Without Using Third Variable

/*    Swap the values of two variables without using third variable   */

 Method 1 (Using Arithmetic Operators)

#include<stdio.h>
int main ( )
{
 int a;
 int b;
 printf("Type value of A : ");
 scanf("%d",&a);
 printf("\nType value of B : ");
 scanf("%d",&b);
  a = a + b;
  b = a - b;
  a = a - b ;
 printf("A : %d",a);
 printf("\nB : %d",b);
 return 0;
}

Method 2 (Using Multiplication and division Operators)

#include<stdio.h>
 int main ( )
{
  int a;
  int b;
  printf("Type value of A : ");
  scanf("%d",&a);
  printf("\nType value of B : ");
  scanf("%d",&b);
  a=a*b;

  b=a/b;

  a=a/b;
 printf("A : %d",a);
 printf("\nB : %d",b);
 return 0;
}

Method 3 (Using Bitwise XOR)

#include<stdio.h>
 int main ( )
{
  int a;
  int b;
  printf("Type value of A : ");
  scanf("%d",&a);
  printf("\nType value of B : ");
  scanf("%d",&b);  

  a=a^b;

  b=a^b;

  a=a^b;
 printf("A : %d",a);
 printf("\nB : %d",b);
 return 0;
}

Method 4 (Using Functions and Pointers)

#include<stdio.h>

void swap(int *x,int *y)

{

  if(*x==*y) 

  return;

  *x = *x +  *y;

  *y = *x  -  *y;

  *x = *x  -  *y;

}

 int main ( )
{
  int a;
  int b;
  printf("Type value of A : ");
  scanf("%d",&a);
  printf("\nType value of B : ");
  scanf("%d",&b);  

  printf("Before Swapping A=%d B=%d",a,b);

  swap(&a,&b);
  printf("After   Swapping A=%d B=%d",a,b);
  return 0;
}

Method 5 (Using Assignment Operator)

void main(){

    int a=10,b=30;

    a=a+b-(b=a);

    //10+30-(10)  a becomes 30

    // b is assigned with 10 in the same line of code

    printf("a= %d\nb=  %d",a,b);

}

Method 6 (Using Bitwise Operator)



#include<stdio.h>
void main()
{   
int a=14,b=4;   
a=b-~a-1;   
b=a+~b+1;  
a=a+~b+1;   
printf("a=%d\nb=  %d",a,b);
}