#include<iostream>
using namespace std;
int main() {
	int x;
	char a;
	cin >> x >> a;
	if (x <= 1000 && a == 'n') cout << 8;
	else if (x <= 1000 && a == 'y') cout << 13;
	else if (x > 1000 && x / 500 != 0 && a == 'n') cout << 8 + (((x - 1000) / 500) + 1) * 4;
	else if (x > 1000 && x / 500 != 0 && a == 'y') cout << 13 + (((x - 1000) / 500) + 1) * 4;
	else if (x > 1000 && x / 500 == 0 && a == 'n') cout << 8 + ((x - 1000) / 500) * 4;
	else cout << 13 + ((x - 1000) / 500) * 4;
	return 0;
}