#include <iostream>
using namespace std;
int main() {
int N, N2;
cin >> N;
N2 = N;
if(N2 !=N){
cout << "NO";
}else{
cout << "YES";
}
return 0;
}
I2luY2x1ZGUgPGlvc3RyZWFtPgp1c2luZyBuYW1lc3BhY2Ugc3RkOwoKaW50IG1haW4oKSB7CglpbnQgTiwgTjI7CgljaW4gPj4gTjsKCU4yID0gTjsKCWlmKE4yICE9Til7CgkJY291dCA8PCAiTk8iOwoJfWVsc2V7CgkJY291dCA8PCAiWUVTIjsKCX0KCXJldHVybiAwOwp9