#include "bits/stdc++.h"

#define int long long
using namespace std;
using ll = long long;
using P = pair<ll, ll>;
const ll INF = (1LL << 61);
ll mod = 1000000007;



signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int N; cin >> N;
	if (N % 2 == 1)cout << 1 << endl;
	else cout << N / 2 + 1<< endl;
	return 0;
}