toggleString.java

import java.util.*;

class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String input = scanner.nextLine();
        String convertedString = convertCase(input);
        System.out.println(convertedString);
        scanner.close();
    }

    public static String convertCase(String str) {
        StringBuilder result = new StringBuilder();
        for (int i = 0; i < str.length(); i++) {
            char ch = str.charAt(i);
            if (Character.isUpperCase(ch)) {
                result.append(Character.toLowerCase(ch));
            } else if (Character.isLowerCase(ch)) {
                result.append(Character.toUpperCase(ch));
            } else {
                result.append(ch); 
                // If it's not a letter, keep it unchanged
            }
        }
        return result.toString();
    }
}