#include <bits/stdc++.h>

int main() {

  int v[16] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  int ans = 0;

  for(int i = 1; i <= 12; ++i) {
    for(int j = 1; j <= v[i]; ++j) {
      if( i == (j%10 + j/10) ) {
	ans += 1;
      }
    }
  }

  std::cout << ans << std::endl;

  
  return 0;
}