import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
	
	public static void main(String[] args){
		
		BufferedReader insBR = new BufferedReader(new InputStreamReader(System.in));
		String strLine = null;
		try {
			strLine = insBR.readLine();
			
		} catch (IOException e) {
			// TODO ????????????????????? catch ????????????
			e.printStackTrace();
		}
		//????????????????§£???????????????????´?
		char[] ary = strLine.toCharArray();
		//?°???????????????????????????§????????????????????????????´?
		for(int i = 0; i < ary.length; i++){
			if(Character.isLowerCase(ary[i])){
				ary[i] = Character.toUpperCase(ary[i]);
			}else{
				ary[i] = Character.toLowerCase(ary[i]);
			}
		}
		String strNewLine = new String(ary);
		System.out.println(strNewLine);
	}

}
/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