import calendar, math

cnt = 0

for i in range(1, 13):
  monthdays = calendar.monthrange(2015, i)
  dd1 = (monthdays[1])

  for n in range(1, dd1+1):
    
    if( n < 10):
      day10 = 0
      day1 = n
      
    else:
      day10 = math.floor( n/10 )
      day1 = n - day10*10

    if( i == day10 + day1):
       cnt = cnt+1
       
print(cnt)