GrabAndGo

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Numerics;

namespace _17_04_GrabAndGo
{
    class GrabAndGo
    {
        static void Main(string[] args)
        {
            var input = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();

            int number = int.Parse(Console.ReadLine());


            if (input.Contains(number))
            {
                int index = Array.LastIndexOf(input, number);
                BigInteger sum = input.Take(index).Sum();

                Console.WriteLine(sum);
            }
            else
            {
                Console.WriteLine("No occurrences were found!");
            }
        }
    }
}