#include <stdio.h>
int main(void){
int i, j, c;
int m [] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

   c = 0;
   for ( i = 0; i < 12; i++){
       for( j = 1; j < m[i] + 1; j++){
           if ( i == j / 10 + j % 10){
               c++;
           }
       }
   }
   printf("%d\n",c);
   return 0;
}