题解 100% AC

#include<bits/stdc++.h>
using namespace std;
string s;
string to8(int n){
    if(n==0)return"";
    to8(n/8);
    s+=n%8;
    return s;
}
int main(){
    int n;
    cin>>n;
    if(n==0)cout<<"YES";
    else{
        string x=to8(n);
        reverse(s.begin(),s.end());
        if(x==s)cout<<"YES";
        else cout<<"NO";
    }
    return 0;
}