All of the logic gates we've been using (AND, XOR, OR, etc) are part of every programming languages as bitwise operators. You've probably seen them before - here they are in JavaScript:

• & is AND
• || is OR
• ^ is XOR

And so on. In this video we dive in head-first and answer a pretty common interview question:

Create a routine that adds two positive integers together without using mathematic operators.

I got asked this once and drew a complete blank as I had no idea and let the interviewer know that. They tried to offer me clues but I was beyond any kind of help, in a completely foreign land. I knew absolutely nothing about binary!

If this is you, buckle up cause here we go!

The Code

Here's the code we'll be cycling on for the video:

const add =function(x,y) {
  //iterate until there is no carry
  let should_carry = null;
  while(should_carry !== 0){
    should_carry = x & y;
    x = x ^ y;
    y = should_carry << 1;
  }
  return x;
}
console.log(add(27,15));