Arrays - 10_SequenceOfGivenSum

using System;

/*
 * 10. Write a program that finds in given array of integers a sequence of given sum S (if present).
 * Example:  {4, 3, 1, 4, 2, 5, 8}, S=11 -> {4, 2, 5}
 */
class SequenceOfGivenSum
{
    static void Main()
    {
        int n;
        int S;
        int currentSum = 0;
        int firstIndex = 0;
        int lastIndex = 0;

        Console.Write("Number of array elements: ");
        string strN = Console.ReadLine();

        Console.Write("S = ");
        string strS = Console.ReadLine();

        if (!int.TryParse(strN, out n) || !int.TryParse(strS, out S))
        {
            Console.WriteLine("Invalid numbers!");
        }
        else
        {
            int[] array = new int[n];

            // Get all array values
            for (int i = 0; i < n; i++)
            {
                Console.Write("Please enter array element: ");
                array[i] = int.Parse(Console.ReadLine());
            }

            currentSum = array[0];

            for (int i = 0; i < array.Length; i++)
            {
                for (int j = i + 1; j < array.Length; j++)
                {
                    currentSum += array[j];

                    if (currentSum == S)
                    {
                        firstIndex = i + 1;
                        lastIndex = j;
                    }
                }

                currentSum = 0;
            }

            if (firstIndex > 0 && lastIndex > 0)
            {
                Console.WriteLine("The sequence with sum {0} is: ", S);
                Console.Write("{ ");

                for (int i = firstIndex; i <= lastIndex; i++)
                {
                    if (i == lastIndex)
                    {
                        Console.Write("{0}", array[i]);
                    }
                    else
                    {
                        Console.Write("{0}, ", array[i]);
                    }
                }

                Console.WriteLine(" }");
            }
            else
            {
                Console.WriteLine("There is no sequence with sum {0} in the array.", S);
            }
        }
    }
}