4-5

#include <iostream>
using namespace std;
int main()
/*{
    int N;
    cin >> N;
    if ((N < 1) || (N > 9))
        cout << "N is wrong: " << N;
    else
        for (int i = 0; i < N; i++) {
            for (int j = 1; j < i+2; j++)
                cout << j << " ";
            cout << endl;
        }
}
*/

{
    char ltr;
    cin >> ltr;
    ltr = tolower(ltr);
    if (ltr > 96 && ltr < 123) {
        if (ltr == 97 || ltr == 101 || ltr == 105 || ltr == 111 || ltr == 117 || ltr == 121)
            cout << "vowel";
        else
            cout << "consonant";
    }
    else
        cout << "Not letter";
}