Condense Array to Number

using System;
using System.Linq;

namespace P08_Condense_Array_to_Number
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] nums = Console.ReadLine()
                .Split()
                .Select(int.Parse)
                .ToArray();
            int[] condensed = new int[nums.Length - 1];

            if(nums.Length == 1)
            {
                Console.WriteLine(nums[0]);
                return;
            }
            for (int i = 0; i < nums.Length; i++)
            {
                for (int j = 0; j < condensed.Length - i; j++)
                {
                    condensed[j] = nums[j] + nums[j + 1];
                }
                condensed = nums;
            }
            Console.WriteLine(condensed[0]);
        }
    }
}