Hkhv喜欢二进制 NBUT - 1666

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<string>
#include<cmath>
using namespace std;

int main()
{
    string s;
    
    while(cin >> s){
        for (int i = 0; i < s.size(); i++)
        {
            if (s[i] > ‘1‘)
            {
                for (int j = i; j < s.size(); j++)
                {
                    s[j] = ‘1‘;
                }
                break;
            }
        }
        // cout << s << endl;
        int ans = 0;
        reverse(s.begin(), s.end());
        for (int i = 0; i < s.size(); i++)
        {
            if (s[i] == ‘0‘) continue;
            else ans += (int)pow((double)2, (double)i);
        }
        printf("%d\n", ans);
    }
    return 0;
}