题解 | 大整数的因子

#include<iostream>
#include<string>
#include<vector>
using namespace std;
int dividstring(string a,int x){
    int carry=0;
    for(int i=0;i<a.size();i++){
        int num=a[i]-'0';
        num+=carry*10;
        carry=num%x;
        a[i]=num/x+'0';
    }
    return carry;
}
int main(){
    string c;
    while(cin>>c){
        if(c=="-1") break;
        vector<int>a;
        for(int k=2;k<=9;k++){
            if(dividstring(c,k)==0){
                a.push_back(k);
            }
        }
        if(a.size()==0){
            cout<<"none"<<endl;
        }
        else{
            for(int i=0;i<a.size();i++){
                if(i!=a.size()-1){
                    cout<<a[i]<<" ";
                }
                else{
                    cout<<a[i];
                }
            }
            cout<<endl;
        }
    }
}