Задача: Цена со скидкой

ApplyDiscounts.cs

using System;
using System.Linq;
using System.Collections.Generic;
					
public class Program
{
	public static int[] ApplyDiscounts(int[] prices) 
	{
		int len = prices.Length;
		var stack = new Stack<int>();

		for (int i = 0; i < len; i++) {
		    while(stack.Any() && prices[stack.Peek()] >= prices[i])
		    {
			prices[stack.Pop()] -= prices[i];
		    }
		    stack.Push(i);
		}

		return prices;
	}
	
	public static void Main()
	{
		Console.WriteLine("UniLecs");
		
		// tests
		Console.WriteLine(string.Join(", ", ApplyDiscounts(new int[] { 8,4,6,2,3 }))); // 4,2,4,2,3
		Console.WriteLine(string.Join(", ", ApplyDiscounts(new int[] { 1,2,3,4,5 }))); // 1,2,3,4,5
	}
}