import calendar
C=0
for i in range(1,12):
    cal = calendar.month(2015, i)
    #print(cal)
    B=int(cal.split()[-1])
    #print(B)
    for j in range(1,B):
        #print(j)
        ten=int(j/10)
        #print(ten)
        one=j-(ten*10)
        #print(ten,one)
        A=ten+one
        if i==A:
            #print(i,j)
            C+=1
print(C)