N=int(raw_input())
#2014/7/23 Wed
cur = 3
year = 2014
interval = -1
cnt =0
for i in range(1,3000):
    offset = 365%7
    if (year+i) %4 == 0:
        offset+=1
    if (year+i)%100 == 0:
        offset -=1
    if (year+i)%400 == 0:
        offset +=1
    cur+=offset
    cur%=7
    if cur == 3:
        cnt+=1
        if i %400 ==0:
            interval = i
            break
#print interval,cnt
times=(N-2014)/interval
ans = times*cnt
year= 2014+times*interval
cur=3
for i in range(year+1,N+1):
    offset = 365%7
    if i %4 == 0:
        offset+=1
    if i%100 == 0:
        offset -=1
    if i%400 == 0:
        offset +=1
    cur+=offset
    cur%=7
    if cur == 3:
        ans+=1
print ans