#include<stdio.h>

int main(){
  int month[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
  int i,j,count;

  count = 0;
  for(i=1;i<13;i++){
    for(j=1;j<month[i];j++){
       if(j/10+j%10==i) count++;
      }
    }
    printf("%d\n",count);

    return 0;
}