PareParePare.cs

using System;
using System.Collections.Generic;

class Program
{
    static List<int> pare;

    static void Main(string[] args)
    {
        pare = new List<int>();

        Console.WriteLine("Unesi pare koje imas, ako je to-to, pritisni enter na prazno:");

        while (true)
        {
            string str = Console.ReadLine();

            if (string.IsNullOrEmpty(str))
                break;
            else if (int.TryParse(str, out int inPare))
                pare.Add(inPare);
            else
                Console.WriteLine("Nisu pare to lele. Probaj opet..");
        }

        // Sort from largest to smallest
        pare.Sort();
        pare.Reverse();

        Console.WriteLine("Ok, imas: ");

        for (int i = 0; i < pare.Count; i++)
        {
            Console.Write(pare[i]);

            if (i != pare.Count - 1)
                Console.Write(", ");
        }

        Console.WriteLine("\n\nUnesi sumu koju oces da platis:");

        int target;
        while (true)
        {
            string sumaStr = Console.ReadLine();

            if (int.TryParse(sumaStr, out target))
                break;
            else
                Console.WriteLine("Nije broj, probaj opet");
        }

        Console.WriteLine("");

        int total = 0;
        foreach (var para in pare)
            total += para;

        // Early out if not enough
        if (total < target)
        {
            Console.WriteLine("Eeee nemas dovoljno!");
            Console.ReadKey();
            return;
        }

        List<int> result = new List<int>();

        int remaining = target;
        int lastOverlapRemaining = target;

        int currentIndex = 0;
        int lastOverlappingIndex = 0;

        // go down the stack and add everything that fits
        do
        {
            int next = pare[currentIndex];

            if (next <= remaining)
            {
                result.Add(next);
                remaining -= next;
            }
            else
            {
                // remember the index of last that that didn't fit in case of kusur
                lastOverlappingIndex = currentIndex;
                lastOverlapRemaining = remaining;
            }

            currentIndex++;
        }
        while (currentIndex < pare.Count && remaining != 0);

        // KUSUR:
        // if we still have the remainder, we can pay, but kusur
        if (remaining > 0)
        {
            // trace back through the stack and pop those that are less than remaining
            for (int i = result.Count - 1; i >= 0; i--)
            {
                if (result[i] < lastOverlapRemaining)
                    result.RemoveAt(result.Count - 1);
                else
                    break;
            }

            result.Add(pare[lastOverlappingIndex]);

            int kusur = pare[lastOverlappingIndex] - lastOverlapRemaining;

            // Output

            Console.WriteLine("Jbg, ne fituje, ali mozes da platis sa:");

            for (int i = 0; i < result.Count; i++)
            {
                Console.Write(result[i]);

                if (i != result.Count - 1)
                    Console.Write(", ");
            }

            Console.WriteLine("\nI dobijes kusur: " + kusur);

            Console.ReadKey();
            return;
        }

        Console.WriteLine("Mozes da platis sa:");

        for (int i = 0; i < result.Count; i++)
        {
            Console.Write(result[i]);

            if (i != result.Count - 1)
                Console.Write(", ");
        }

        Console.WriteLine();
        Console.ReadKey();
    }
}