[백준] 2744번

import java.util.*;
import java.io.*;

public class Main {
   public static void main(String[] args) throws NumberFormatException, IOException {
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      String inputData = br.readLine();
      
      for (int i = 0; i < inputData.length(); i++) {
         char c = inputData.charAt(i);
         if (Character.isUpperCase(c))
            System.out.print(String.valueOf(c).toLowerCase());
         else
            System.out.print(String.valueOf(c).toUpperCase());
      }
   }
}