PAT1039

#include<string>#include<iostream>#include<algorithm>using namespace std;const int num=10010;string str[num];int judge(string &str){string::iterator it=str.begin();while(str.size()>0&&*(str.begin())=='0')str.erase(str.begin());if(str.size()==0)return 0;elsereturn 1;}int cmp(string str1,string str2)//4324524  432{string::iterator it1=str1.begin();string::iterator it2=str2.begin();while(1){while(it1!=str1.end()&&it2!=str2.end()){if(*it1!=*it2)return *it1<*it2;it1++;it2++;}if(it1==str1.end()&&it2==str2.end())return 1;else if(it1!=str1.end()){it2=str2.begin();}else if(it2!=str2.end()){it1=str1.begin();}}}int main(){int n;//freopen("in.txt","r",stdin);cin>>n;for(int i=0;i<n;i++)cin>>str[i];sort(str,str+n,cmp);int i;for(i=0;i<n;i++)if(judge(str[i]))break;if(i==n)cout<<0<<endl;else{for(;i<n;i++)cout<<str[i];cout<<endl;}return 0;}