Solution: Counting Money

using System;
using System.Collections.Generic;
class Program
{
    /// <summary>
    /// This method finds the minimum number of coins needed.
    /// </summary>
    /// <param name="v">Total amount.</param>
    /// <param name="coinsAvailable">Coins available in the machine.</param>
    /// <returns>An array of total coins needed.</returns>
    public static int[] FindMinCoins(int v, int[] coinsAvailable)
    {
        // Initialize result
        List<int> result = new List<int>();
        int n = coinsAvailable.Length;
        // Traverse through all available coins
        for (int i = n - 1; i >= 0; i--)
        {
            while (v >= coinsAvailable[i])
            {
                v -= coinsAvailable[i];
                result.Add(coinsAvailable[i]);
            }
        }
        return result.ToArray();
    }
    // Main program to test the above code
    public static void Main(string[] args)
    {
        int[] coinsAvailable = { 1, 5, 10, 25 }; // The available coins are in increasing order
        int[] result = FindMinCoins(19, coinsAvailable);
        Console.WriteLine("[" + string.Join(", ", result) + "]");
    }
}