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 JAVA (judge verdict: Wrong Answer)

import java.util.Scanner;
public class Main { 
    public static void main(String[] args) {  
        try (Scanner sc = new Scanner(System.in)) { 
            String line = sc.nextLine(); 
            String answer = ""; 
            int length = line.length(); 
            for (int i = 0; i < length; i++) { 
                char ch = line.charAt(i); 
                if(Character.isLowerCase(ch) == true){
                    ch = Character.toUpperCase(ch);
                } else if(Character.isLowerCase(ch) == false){
                    ch = Character.toLowerCase(ch);
                }
            } 
            System.out.println(answer); 
        } 
    }
}