#include <iostream>
using namespace std;

int main() {
    // Input the cost per kilogram of potato
    int X;
    cin >> X;

    // Calculate the total cost for 2 kilograms of potato
    int total_cost = X * 2;

    // Check if Sunny can buy 2 kilograms of potato
    if (total_cost <= 100) {
        cout << "YES\n";
    } else {
        cout << "NO\n";
    }

    return 0;
}