Swapping two values without using 3rd variable

 #include<stdio.h>

#include<conio.h>

void main()

{

           int a,b;

           clrscr();

    printf("enter the value of a and b \n");

    scanf("%d%d",&a,&b);

    printf("before swiping value of a=%d & b=%d\n",a,b);

    

   

            

           a=a*b;

           b=a/b;

           a=a/b;

    

    printf("after swiping value of a=%d & b=%d",a,b);

    

    getch();

}

Output : 

enter the value of a and b

45

34

before swiping value of a=45 & b=34

after swiping value of a=34 & b=45

[Process completed (code 10) - press Enter]