#include<stdio.h>
#include<algorithm>
using namespace std;
int m[]={31,28,31,30,31,30,31,31,30,31,30,31};
int main(){
	int ret=0;
	for(int i=0;i<12;i++){
		for(int j=1;j<=m[i];j++){
			if(i+1==j/10+j%10)ret++;
		}
	}
	printf("%d\n",ret);
}