import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.lang.StringBuilder;
public class Main {
	public static void main(String[] args) throws Exception{
		BufferedReader sc = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder sb = new StringBuilder();
		char[] ch = sc.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