#include <iostream>

int main(){
    int a,b,c;
    int m[] = {31,29,31,30,31,30,31,31,30,31,30,31};
    int cnt;
    
    for(int i=0;i<12;i++){
        for(int j=1;j<m[i]+1;j++){
            a = j / 10;
            b = j % 10;
            c = a + b;
            if(c==(i+1)){
                cnt++;
            }
        }
    }
    std::cout << cnt << std::endl;
}