How to swap two numbers without using temp variables or arithmetic operations?

Question

This equation swaps two numbers without a temporary variable, but uses arithmetic operations:

a = (a+b) - (b=a);

How can I do it without ar

Answer 1

Multiplication and division can also be used.

 int x = 10, y = 5;

 // Code to swap 'x' and 'y'
 x = x * y;  // x now becomes 50
 y = x / y;  // y becomes 10
 x = x / y;  // x becomes 5

Answer 2

C++11 allows to:

• Swap values:

  std::swap(a, b);
  

• Swap ranges:

  std::swap_ranges(a.begin(), a.end(), b.begin());
  

• Create LValue tuple with tie:

  std::tie(b, a) = std::make_tuple(a, b);
  
  std::tie(c, b, a) = std::make_tuple(a, b, c);
  

Answer 3

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

This is simple yet effective....

Answer 4

In C this should work:

a = a^b;
b = a^b;
a = a^b;

OR a cooler/geekier looking:

a^=b;
b^=a;
a^=b;

For more details look into this. XOR is a very powerful operation that has many interesting usages cropping up here and there.