#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <cmath>
#include <cstdlib>
#include <cstdio>
#define N 1000
#define re(i,n) for(int i=0;i<(n);i++)
using namespace std;

typedef long long ll;

int main(void){
	int a[]={31,28,31,30,31,30,31,31,30,31,30,31};
	int c=0;

	re(i,12) re(j,a[i]+1) if(i+1==j/10+(j%10)) c++;
	cout<<c<<endl;
	return 0;
}