coin_change

public static int coinChange(int[] coins, int amount){
  return recursionHelper(coins, amount);
}

private static int recursionHelper(int[] coins, int remaining) {
    if (remaining == 0) return 0;
    if (remaining < 0) return -1;

    int minCount = Integer.MAX_VALUE;
    for (int coin: coins){
        int count = recursionHelper(coins, remaining - coin);
        if (count == - 1) continue;
        minCount = Math.min(minCount, count + 1);
    }

    return minCount == Integer.MAX_VALUE ? - 1 : minCount;
}