#include <iostream>
#include <string>

using namespace std;

char convert(char in) {
    if ('a' <= in && in <= 'z') {
        return in - 'a' + 'A';
    } else {
        return in - 'A' + 'a';
    }
}

int main() {
    string password;
    cin >> password;

    for (unsigned int i = 0; i < password.size(); i++) {
        password[i] = convert(password[i]);
    }

    cout << password << endl;

    return 0;
}