/* ITP1_8_A */
import java.io.*;

class Main
{
  public static void main(String[] args)
  {
    try{
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      StringBuilder sb = new StringBuilder();

      String str = br.readLine();

      for(char c : str.toCharArray()){
        if(Character.isUpperCase(c)){
          sb.append(Character.toLowerCase(c));
        }else if(Character.isLowerCase(c)){
          sb.append(Character.toUpperCase(c));
        }else {
          sb.append(c);
        }
      }
      System.out.println(sb);

    }catch(Exception e){
      System.out.println(e);
    }
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz