#include "bits/stdc++.h"
//#include <boost/multi_array.hpp>
//#include <boost/optional.hpp>
//#include <boost/range/irange.hpp>
//#include <boost/range/algorithm.hpp>
//#include <boost/range/adaptors.hpp>
using namespace std;
using ll = long long;
using ld = long double;
using P = pair<int, int>;
#define rep(i, n) for (int i = 0; i < (n); i++)
#define rep2(i, x, n) for (int i = x; i < (n); i++)
#define all(n) begin(n), end(n)
struct cww {
    cww() {
        ios::sync_with_stdio(false);
        cin.tie(0);
    }
} star;
const long long INF = numeric_limits<long long>::max();

long long gcd(long long a, long long b) {  // 2つの場合の最大公約数
    if (b == 0) {
        return a;
    } else {
        return gcd(b, a % b);
    }
}

void Main() {  //う　し　た　ぷ　に　き　あ　く　ん　笑
    int a;
    cin >> a;
    if (a >= 3) {
        cout << "YES" << endl;
    } else {
        cout << "NO" << endl;
    }
}  //う　し　た　ぷ　に　き　あ　く　ん　笑

int main() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << std::fixed << std::setprecision(15);
    Main();
    return 0;
}