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 <stdio.h>
#include <ctype.h>

int main(void){
    char ch;
    
    while(1){
        scanf("%c",&ch);
        
        if(ch == "\n")break;
        if(islower(ch)) ch = toupper(ch);
        else if(isupper(ch)) ch = tolower(ch);
        printf("%c",ch);
    }
    printf("\n");
}