#include<stdio.h>

int day_check(int mon){
	if (mon == 2)
	return 28;

	else if (mon == 4 ||mon == 6 ||mon == 9 ||mon == 11)
	return 30;

	else
	return 31;
}

int main(void)
{
int day,i,mon,total=0;

for (mon=1 ; mon<=12 ; mon++){
	day = day_check(mon);

	for(i=1 ; i<=day ; i++){
	int x,y;
	x=i/10;
	y=i%10;

		if(mon==(x+y))
			total++;
	}
}
	printf("%d\n",total);
return 0;
}