A price $15.90 can be reflected as 1590 cent. It's convenient when you don't need more than two decimal points accuracy and it prevents some floating point weirdness like 0.1 + 0.2 ≠ 0.3.
To split one integer into two at the third but last digit, do
const price = 1590;
const cent = price % 100;
const dollars = price / 100 | 0;The bitwise or with 0 in Javascript trims the decimal part and leaves the integer part of any number.