/**
*/

//スキャナつかうため

import java.util.Scanner;

public class Main {
	// プログラムのエントリポイント
	public static void main(String[] args) {
		// 入力ストリームの生成
		Scanner sc = new Scanner(System.in);
		String moji = sc.nextLine();
		char [] chmoji = new char [moji.length()];
		for (int i =0; i<moji.length(); i++){
			 chmoji[i]   = moji.charAt(i);
			  boolean kekka = Character.isUpperCase(chmoji[i]);
			 if (kekka == true ){
				 chmoji[i] = Character.toLowerCase(chmoji[i]);
			 }else {
				 chmoji[i] = Character.toUpperCase(chmoji[i]);
			 }
			 System.out.print(chmoji[i]);

		}
		System.out.println();
	}
}
/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