EqualPairs

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

namespace EqualPairs
{
    class EqualPairs
    {
        static void Main(string[] args)
        {
            int chisloto = int.Parse(Console.ReadLine());

            int counter = 0;

            var sum = 0;
            var currentSum = 0;

            var biggestDiff = 0;

            bool equalSums = true;
            bool haveASum = false; //flag

            for(int i = 0; i < chisloto * 2; i++)
            {
                if (counter < 2)
                {
                    int number = int.Parse(Console.ReadLine());
                    currentSum += number;
                    counter++;
                }
                if(haveASum)
                {
                    if(sum != currentSum && counter == 2)
                    {
                        equalSums = false;
                        var difference = Math.Abs(sum - currentSum);
                        if(biggestDiff < difference)
                        {
                            biggestDiff = difference;
                        }
                        sum = currentSum;
                        currentSum = 0;
                    }
                    else if(counter == 2)
                    {
                        sum = currentSum;
                        currentSum = 0;
                    }
                }
                else if(counter == 2 && !haveASum)
                {
                    haveASum = true;
                    sum = currentSum;
                    currentSum = 0;
                }

                if(counter == 2)
                {
                    counter = 0;
                }
            }

            if(equalSums)
            {
                Console.WriteLine("Yes, value={0}" , sum);
            }
            else
            {
                Console.WriteLine("No, maxdiff={0}" , biggestDiff);
            }
        }
    }
}