using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

    }

    public int[] TwoSum(int[] nums, int target) {

        for (var i = 0; i < nums.Length; i++)

        {

            int required = target - nums[i];

            var match = nums.Select(

                (n, j) => 

                    n == required && j != i

                    : j 

                    ? null);

            if (match == null)

                continue;

            var indicies = new[] { i, match };

            return indicies;

        }

        return null;

    }

}