n=gets.to_i-2015

memo=Array.new(400,0)

diff=0
400.times{|dy|
    y=dy+2015
    diff+=(((y%4==0 && y%100!=0) || y%400==0) ? 2 : 1)
    memo[dy]=diff%7==0 ? 1 : 0
}

ans=memo.inject(:+)*(n/400)
p ans+memo[0..(n%400)].inject(:+)