看到就是福，（内有小惊喜搞笑图片，解压）

#include <bits/stdc++.h>
using namespace std;

int main() {
   
    
    unsigned long long x, num;
    cin >> x;
    
    if (x <= 0) {
        cout << "NO" << endl;
        return 0;
    }
    
    num = x;
    while (num % 2 == 0) {
        num /= 2;
    }
   
    if (num == 1) 
        cout << "YES" << endl;
    else 
        cout << "NO" << endl;
    
    return 0;
}

由于屏幕前的你有可能或者备考三级时更方便（怕被老师发现抄题解）所以我就没写注释，毕竟平时你们写题也不会写注释。***
在这里我给大家发送一些“可爱”的小图片（直接CTRL+C CTRL + A复制粘贴在百度上输出网址）

https://image.baidu.com/search/detail?ct=503316480&z=0&tn=baiduimagedetail&ipn=d&cl=2&cm=1&sc=0&sa=vs_ala_img_datu&lm=-1&ie=utf8&pn=2&rn=1&di=7646086322926387201&ln=0&word=%E6%90%9E%E7%AC%91%E5%9B%BE%E7%89%87&os=2094431559%2C149092035&cs=1201924260%2C950589303&objurl=http%3A%2F%2Fsafe-img.xhscdn.com%2Fbw1%2F13b3af82-557c-4590-837a-e8c2f2c60bdd%3FimageView2%2F2%2Fw%2F1080%2Fformat%2Fjpg&bdtype=0&simid=1201924260%2C950589303&pi=0&adpicid=0&timingneed=&spn=0&is=2094431559%2C149092035&lid=d3f97d2301334e70

https://image.baidu.com/search/detail?ct=503316480&z=0&tn=baiduimagedetail&ipn=d&cl=2&cm=1&sc=0&sa=vs_ala_img_datu&lm=-1&ie=utf8&pn=4&rn=1&di=7646086322926387201&ln=0&word=%E6%90%9E%E7%AC%91%E5%9B%BE%E7%89%87&os=3220007929%2C280734215&cs=513149238%2C1906834665&objurl=http%3A%2F%2Fwww.ajesmm.com%2Fwp-content%2Fuploads%2Ftupianbd%2F0%2F253%2F513149238%2F1906834665.jpg&bdtype=0&simid=513149238%2C1906834665&pi=0&adpicid=0&timingneed=&spn=0&is=0%2C0&lid=d3f97d2301334e70

https://image.baidu.com/search/detail?adpicid=0&b_applid=7609181892727970352&bdtype=0&commodity=&copyright=&cs=497732493%2C2385684929&di=7646086322926387201&fr=click-pic&fromurl=http%253A%252F%252Fwww.lantian.ccoo.cn%252Fforum%252Fthread-1571792-1-1.html&gsm=1e&hd=&height=0&hot=&ic=&ie=utf-8&imgformat=&imgratio=&imgspn=0&is=0%2C0&isImgSet=&latest=&lid=d3f97d2301334e70&lm=&objurl=https%253A%252F%252Fimages.pccoo.cn%252Fbbs%252F2010311%252F201031117244961.jpg&os=1163706262%2C177502274&pd=image_content&pi=0&pn=10&rn=1&simid=497732493%2C2385684929&tn=baiduimagedetail&width=0&word=%E6%90%9E%E7%AC%91%E5%9B%BE%E7%89%87&z=