Javascript Array Random Got Zero -

i'm trying random number between 0 , array.length. have this:

getrandom() {   const cars = object.keys(this.index);   const randomint = math.floor(math.random() * cars.length);   return cars[randomint]; } 

i ran few times , found 0 in 1 of results getrandom(). there not key in this.index object named 0.

is math function wrong?

update

after reading comments, , know getrandom() not wrong. have reset() function if guys can @ it.

reset() {   const cars = object.keys(this.index);   let = cars.length;   while (i--) {     this.index[cars[i]] = 0;   } } 

is possible i'm adding new key 0 @ this.index object?

i can't see actual problem here.

object.keys turn named keys numbers (look here https://developer.mozilla.org/de/docs/web/javascript/reference/global_objects/object/keys), numbers starts 0.

so function, wrote yourselv, return an:

random number between 0 , array.length