#include <stdio.h>


int main() {
    int i, j;
    int month[13] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
    int ans = 0;
    for (i = 1; i <= 12; ++i) {
        for (j = 1; j <= month[i]; ++j) {
            if (i == j % 10 + j / 10) {
                ans++;
            }
        }
    }
    printf("%d\n", ans);
    return 0;
}