01. Reverse String

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

class ReverseString
{
    static void Main()
    {
        string input = Console.ReadLine();

        ////Using the build-in reverse method
        //char[] inputChars = input.ToCharArray();
        //Array.Reverse(inputChars);
        //Console.WriteLine(new string (inputChars));

        //Without using the build-in reverse method
        char[] inputChars = input.ToCharArray();
        StringBuilder sb = new StringBuilder();
        for (int i = input.Length - 1; i >= 0; --i)
        {
            sb.Append(inputChars[i]);
        }
        Console.WriteLine(sb.ToString());
    }
}