import java.util.ArrayList;
import java.util.Scanner;
public class TogglingCases {
private static final int BIG_LETTER = 0;
private static final int LITTLE_LETTER = 1;
private static final int OTHERS = 2;
private static Scanner sc = new Scanner(System.in);
private static ArrayList<String> result = new ArrayList<String>();
public static void main(String[] args) {
//1行の入力を受け取る
String input = getInput();
//入力を分割し文字列リストに追加する
setInputStrings(input);
//文字列リストの文字列の小文字大文字を入れ替える
replaceAllStrings();
//文字列リストの文字列を出力する
printAllInputStrings();
}
private static String getInput(){
return sc.nextLine();
}
private static void setInputStrings(String input){
String[] strings = input.split(",");
for(int i = 0; i < strings.length; i++){
result.add(strings[i]);
}
}
private static int isBigLetter(char c){
if(65 <= c && c <= 90){
return BIG_LETTER;
}
else if(97 <= c && c <= 122){
return LITTLE_LETTER;
}
else{
return OTHERS;
}
}
private static String getReplaceString(String str){
String resultString = new String();
for(int i = 0; i < str.length(); i++){
String c = String.valueOf(str.charAt(i));
switch(isBigLetter(c.charAt(0))){
case BIG_LETTER:
resultString = resultString.concat(c.toLowerCase());
break;
case LITTLE_LETTER:
resultString = resultString.concat(c.toUpperCase());
break;
case OTHERS:
resultString = resultString.concat(c);
break;
}
}
return resultString;
}
private static void replaceAllStrings(){
for(int i = 0; i < result.size(); i++){
String str = getReplaceString(result.get(i));
result.set(i, str);
}
}
private static void printAllInputStrings(){
for(int i = 0; i < result.size(); i++){
System.out.printf("%s", result.get(i));
if(i < result.size() - 1){
System.out.printf(",");
}
}
System.out.println();
}
}