d = 6
ds = [0]*400
for i in xrange(400):
    d = (d + (i%4 if i%4 > 0 else 1 if i%100 < 1 else 2))%7
    ds[i] = d
N = int(raw_input())-2000
print N/400*57+ds[:N%400].count(3)-3