#!/usr/bin/env python3
# %%
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

from datetime import datetime

# %%
N = int(read())

# %%
answer = 0
if N > 2800:
    n = N // 2800 - 1
    N -= 2800 * n
    answer += 400 * n

today = datetime(2014, 7, 23)
for year in range(2015, N + 1):
    day = datetime(year, 7, 23)
    if day.weekday() == today.weekday():
        answer += 1


# %%
print(answer)