How does % sign work in javascript

Question

How does % sign work in javascript. Following code gives output 0/1.

for(var i= 0; i<10;i++){
   console.log(isOdd(i))
}
function isOdd(num) { return num % 2;}

[remainder operator](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators#Remainder) — Jaromanda X, Jul 28 '17 at 08:46
possible duplicate of https://stackoverflow.com/questions/2664301/how-does-modulus-divison-work — Avnesh Shakya, Jul 28 '17 at 08:47

score 0 · Answer 1 · answered Jul 28 '17 at 08:49

a%b

Its the modulo operator. It trys to put the biggest multiple of b into a, then returns the rest of it:

2%3 /*3 fits 0 times, remainder is */ 2
6%5 /* 5 fits once, remainder is */ 1
16%5 /* 5 fits three times, remainder is */ 1

Its really useful for endless arrays, so if you go over the max index, start again at 0, which can be written like this:

i++;
if(i>=array.length) i=0;

Can be shortened to:

i=(i+1)%array.length;

1 Answers1