CSP-JT1奇葩做法玄关求调

#include<bits/stdc++.h>
using namespace std;
int main(){
    freopen("number.in","r",stdin);
    freopen("number.out","w",stdout);
    string s;
    cin>>s;
    sort(s.begin(),s.end());
    int t=s.find('9');
    for(char c='8';c>='0';c--){
        if(t!=-1) break;
        else t=s.find(c);
    }
    for(int i=t;i>=0;i--){
        if(isdigit(s[i])) cout<<s[i];
        else break;
    }
    return 0;
}