简单的办法

#include <bits/stdc++.h>
using namespace std;
bool hw(int x){
    int n=0,m=x;
    while(m){
        n=n*8+m%8;
        m/=8;
    }
    if(n==x) return 1;
    return 0;
}
int main(){
    int a;
    cin>>a;
    if(hw(a)) cout<<"YES";
    else cout<<"NO";
    return 0;
}