using System;

​

namespace NBaseToDecimalConverter

{

    class Program

    {

        static void Main(string[] args)

        {

            Console.Write("Enter the base N (2 <= N <= 10): ");

            int N = int.Parse(Console.ReadLine());

​

            Console.Write($"Enter the {N}-base number: ");

            string nBaseNumber = Console.ReadLine();

​

            Console.WriteLine($"The {nBaseNumber} in decimal is {ConvertToDecimal(nBaseNumber, N)}");

        }

​

        static int ConvertToDecimal(string nBaseNumber, int N)

        {

            int decimalNumber = 0;

​

            for (int i = nBaseNumber.Length - 1; i >= 0; i--)

            {

                int digit = int.Parse(nBaseNumber[i].ToString());

                decimalNumber += digit * (int)Math.Pow(N, nBaseNumber.Length - 1 - i);

            }

​

            return decimalNumber;

        }

    }

}

​