using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

// Given an array of integers, Return indices of two numbers so that they add to specific target

//You may assume each input have exactly one solution, and you may not use the same element twice

// Given numbers= [2,11,7,15] and target=9

//Because nums[0] + nums[2] i,e 2 +7=9 

// return indices i.e 0 and2.

         int[] array;

         array = new int[] { 2, 11, 7, 15 };

        int[] result = getTarget(array, 9);

        Console.WriteLine(result[0].ToString(),result[1].ToString());

    }

         public static int[] getTarget(int[] nums, int target)

        {

            int[] result = new int[2];

            Dictionary<int, int> dict = new Dictionary<int, int>();

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

            {

                int difference = target - nums[i];

                if (dict.ContainsKey(difference))

                {

                    result[0] = dict[difference];

                    result[0] = i;

​

                }

                else

                {

                    dict.Add(nums[i], i);

                }

​

            }

            return result;

​

        }

}