int task5() {
    string s;
    cin >> s;
    bool k = true;
    for (int i = 0; i < s.length(); i++) {
        if (s[i] != s[s.length() - i - 1]) {
            k = false;
            break;
        }
    }
    (k) ? cout << "yes" : cout << "no";
    return 0;
}

int task4() {
    string s, s1;
    int count = 1;
    getline(cin, s);
    for (char c : s) {
        if (c == ' ') {
            count++;
        }
    }
    cout << count;
    return 0;
}

int task3() {
    char c;
    cin >> c;
    if (c >= 'a' && c <= 'z') {
        c = c - 'a' + 'A';
    }
    else if (c >= 'A' && c <= 'Z') {
        c = c - 'A' + 'a';
    }
    cout << c;
    return 0;
}

int task2() {
    char c;
    cin >> c;
    (c >= 'a' && c <= 'z') ? cout << (c = c - 'a' + 'A') : cout << c;
    return 0;
}

int task1() {
    char c;
    cin >> c;
    (c >= '0' && c <= '9') ? cout << "yes" : cout << "no";
    return 0;
}