Problem:
Toggling Cases

Write a program which converts uppercase/lowercase letters to lowercase/uppercase for a given string.

Input

A string is given in a line.

Output

Print the converted string in a line. Note that you do not need to convert any characters other than alphabetical letters.

Constraints

The length of the input string < 1200

Sample Input

fAIR, LATER, OCCASIONALLY CLOUDY.

Sample Output

Fair, later, occasionally cloudy.

Solution in C# (judge verdict: Accepted)

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

namespace Test
{
    class ForStudy
    {
        public static void Main(string[] args)
        {
            string str = Console.ReadLine();
            for (int i = 0; i < str.Length; i++)
            {
                if (char.IsLower(str[i]))
                {
                    Console.Write(char.ToUpper(str[i]));
                }
                else if (char.IsUpper(str[i]))
                {
                    Console.Write(char.ToLower(str[i]));
                }
                else
                {
                    Console.Write(str[i]);
                }
            }
            Console.WriteLine();
        }
    }
}