using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Collections;

​

namespace CandidateTask

{

    class Program

    {

        static void Main(string[] args)

        {

            // Test array

            int[] a = new int[] {3,-1,-1,2,5,-3,-2,3,1,2,3,4,5};

            Console.WriteLine("Test array: [ " + string.Join(", ", Array.ConvertAll<int, string>(a, n => n.ToString())) + " ]");

            Console.WriteLine("The start index is: " + GetStartIndex(a));

            Console.Read();

        }

        private static int GetStartIndex(int[] a)

        {

            int index=0;

            try{

            //Get the array Length

            int n=a.Length;

            int[] temp= new int[n];

            if(n==0) index= -1; //if array length is '0' return '-1'

            else if(n==1) index= 1; //if array length is '1' return '1'

            else  //Comapre element with all previous elements and check where the sequenece is increasing

            {

                for(int i=1;i<n;i++){

                    for (int j=0;j<i;j++){

                    if((a[i]>a[j]) && temp[i]<temp[j]+1){

                        temp[i]=temp[j]+1;

                    }   

                    }

                }

                for (int i=0;i<n;i++)

                    if(index<temp[i])index=temp[i]; //Return the start of maximum index number

                Console.WriteLine("index array: [ " + string.Join(", ", Array.ConvertAll<int, string>(temp, n => n.ToString()))+ " ]");             

            }

            }

            catch(Exception ex){

                Console.WriteLine("There is an Error in program " + ex.Message + ex.StackTrace);

            }

            return index;

        }

    }

}

​