import java.io.*;
import java.lang.StringBuilder;

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

    char[] ch = br.readLine().toCharArray();
    for(char c : ch){
      String s = String.valueOf(c);
      if (c < 'a')
      sb.append(s.toLowerCase());
      else if(c >= 'a')
      sb.append(s.toUpperCase());
    }
    System.out.println(sb);
  }
}
/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