#include<bits/stdc++.h>
#define dd(x) cerr << #x << endl
using namespace std;
#define int long long
using pii = pair<int, int>;
using vi = vector<int>;
using vii = vector<vector<int>>;
const int inf = 0x3f3f3f3f3f3f3f3fLL;

int rd() {
    int f = 1, val = 0; char ch = getchar();
    while(!isdigit(ch)) f = (ch == '-' ? -1 : 1), ch = getchar();
    while(isdigit(ch)) val = val * 10 + ch - '0', ch = getchar();
    return f * val;
}

vector<int> mon = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

int getMonth(int year, int month) {
    int run = false;
    if(year % 4 == 0) run = true;
    if(year % 100 == 0) {
        run = false;
    }
    if(year % 400 == 0) run = true;
    if(month == 2 && run) return 29;
    return mon[month];
}

void solve() {
    int n = rd();
    int k = 3; // Thursday

    int ans;
    for(int i = 1970; i <= n; i++) {
        ans = 0;
        for(int month = 1; month <= 12; month++) {
            ans += (k + getMonth(i, month) + 6) / 7;
            k = (k + getMonth(i, month)) % 7;
        }
    }
    cout << ans << endl;
}

signed main() {
    int T = 1;
    while(T--) solve();
    return 0;
}