swap two number without the help of other variable

Question

only two variable is used in the program

Answer 1

@Dorian
correct

Answer 2

#include <iostream>
using namespace std;

int main() {

int a=42, b=666;

a=a+b;
b=a-b;
a=a-b;

return 0;
}

Answer 3

int a = 42;
int b = 13;
a ^= b;
b ^= a;
a ^= b;

Or in some compilers:

a ^= b ^= a ^= b;
(Which is very beautiful)

Now a = 13 and b = 42.

Answer 4

great solution, with the xor!!!

Answer 5

what is ^= ?

Answer 6

a ^= b -> a = a ^ b
where ^ is the bitwise xor operator.

Answer 7

a,b=b,a.