const bills_coins = [1000, 500, 100, 50, 20, 10, 5, 2, 1];
const amount = 9725;
let tmp = amount;
for (let i = 0; i < 9; i++) {
console.log(bills_coins[i] + " = " + Math.trunc(tmp / bills_coins[i]));
tmp = tmp % bills_coins[i];
}
/*
run:
"1000 = 9"
"500 = 1"
"100 = 2"
"50 = 0"
"20 = 1"
"10 = 0"
"5 = 1"
"2 = 0"
"1 = 0"
*/