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: Wrong Answer)

using System;
using System.Linq;

public class Hello
{
    public static void Main()
    {
        string str1=Console.ReadLine();
        char [] str=str1.ToCharArray();
        
        string ans="";
        
        foreach(char let in str)
        {
            if(let==','||let=='.'||let==' ')Console.Write(let);
            else Console.Write((char)((int)let^0x20));
            
        }
        Console.WriteLine();
        
    }
}