Javascript | countdown

Question

If i have a variable with 8589934592

Example:

  var a = (8589934592 | 0);
  //a is 0

  var b = (8589934591223 | 0);
  //b is -777

  var c = (85899345999 | 0) 
  //c is 79

  var d = (858993459 | 0);
  //d is 858993459

As i understand, d is the correct but if I try numbers bigger than 858993459

but if I have: for example

  var a = (2147483647 | 0) 
  //a is 2147483647

  var b = (2147483648 | 0) 
  //b is -2147483648

  var c = (2147483649 | 0) 
  //c is -2147483647

I think that its like a negative countdown, how can i avoid this?

Answer 1

You're doing a bitwise operation (simple |: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_Operators#Bitwise_OR)

Because of that, this is done using a 32bit signed int.

Maybe you wanted to double it to use a binary logical operator (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_Operators#Logical_OR)