Given a set of coin denominators, find the minimum number of coins to give a certain amount of change.

makeChange.js

function makeChange (amount) {

  var change = {},
      i = 0,
      coins = makeChange.COINS,
      coin;
  
  while (amount && (coin = coins[i++])) {
    if (amount >= coin) {
      change[coin] = ~~(amount / coin);
      amount %= coin;
    }
  }
  return change;
}

makeChange.COINS = [100, 25, 10, 5, 1];

usage.js

makeChange(199); // {1: 4, 10: 2, 25: 3, 100: 1}