JSFiddle - React, Tailwind, and code Playground

JavaScript

var bills = [5, 10, 20, 50, 100];
var money = mod(235);

function mod(num){
    if (num % 5 === 0){
        return num;
    }else{
        return num + 5 - num % 5
    }
}

function foo(num){
    var index = bills.length - 1;
    var splits = [];
    while (money >= bills[0]){
        if (money >= bills[index]){
           money -= bills[index];
           splits.push(bills[index]);
        }else{
            index--;
        }
    }
    return splits;
}

console.log(foo(money));