Problem:
Reverse Sequence

Write a program which reverses a given string str.

Input

str (the size of str ≤ 20) is given in a line.

Output

Print the reversed str in a line.

Sample Input

w32nimda

Output for the Sample Input

admin23w

Solution in C# (judge verdict: Accepted)

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

namespace AthleteProgramming
{
    class Program
    {
        static void Main()
        {
            char[] str = Console.ReadLine().ToArray();
            Reverse(ref str);
            Console.WriteLine(str);
        }

        static void Reverse(ref char[] str)
        {
            for(int i = 0; i < str.Length / 2; i++)
            {
                Swap(ref str[i], ref str[str.Length-i-1]);
            }
        }

        static void Swap(ref char a,ref  char b)
        {
            char tmp = a;
            a = b;
            b = tmp;
        }
        
    }
}