#include <stdio.h>
int main() {
	int i=10, sum;
	float sum0;
	char a, b, t;
	scanf("%d", &sum);
	scanf("%c%c",&a,&b);
	if (a < b) {
		t = a;
		a = b;
		b = t;
	}
	if (a == 'C' && b != 'B')
		i = 7;
	if (a == 'B')
		i = 8;
	if (a == 'C' && b == 'B')
		i = 6;
	sum0 = sum / 10 * i;
	printf("%f", sum0);
	return 0;
}