import java.io.*;

public class CapString {
        public static void main(String[] args) {
                String MyString = "";
                DataInputStream MyDS = new DataInputStream(System.in);
                int Count;
                char MyCharArray[];
                char MyChar;

                try {
                        MyString = MyDS.readLine();
                }
                catch (Exception IOException) {
                        System.out.println("Nasty error!");
                }

                MyCharArray = MyString.toCharArray();

                for (Count = 0; Count <; MyCharArray.length; Count++) {
                        MyChar = MyCharArray[Count];
                        if (Character.isUpperCase(MyChar)) {
                                MyCharArray[Count] = Character.toLowerCase(MyCharArray[Count]);
                        } else if (Character.isLowerCase(MyChar)) {
                                MyCharArray[Count] = Character.toUpperCase(MyCharArray[Count]);
                        }
                }
                System.out.println(MyCharArray);
        }
}