ans=0
last_dic={1:31,2:28,3:31,4:30,5:31,6:30,7:31,8:31,9:30,10:31,11:30,12:31}
for m in range(1,13):
    last_day=last_dic[m]
    for d in range(1,last_day):
        x=d//10+(d-d//10*10)
        if m==x:
            ans+=1
print(ans)