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: Time Limit Exceeded)

#include<iostream>
#include<cctype>

using namespace std;

int main(int argc, char const *argv[])
{
    char ch;
    while(1) {
        cin >> ch;
        if (ch=='\n') break;
        if (isupper(ch)) cout << tolower(ch);
        else if (islower(ch)) cout << toupper(ch);
        else cout << ch;
    }
    cout << endl;
    return 0;
}