#include    <stdio.h>

int main(void)
{
    int days[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    int m;
    int n;
    int d;

    n = 0;
    for (m = 0; m < 12; m++) {
        for (d = 1; d <= days[m]; d++) {
            if ((m + 1) == ((d / 10) + (d % 10))) {
                n++;
            }
        }
    }
    printf("%d\n", n);

    return 0;
}