#include <bits/stdc++.h>
using namespace std;
 
int main(){
    int n,x,a[100],i;
    cin>>n;
    for(i = 0;i < n;i++){
        cin>>a[i];
    }
    sort(a,a+n);
     
    int p = 0;
    for(i = 0;i < n;i++){
        if(a[i] != 0){
            p = i;
            break;
        }
    }
     
    swap(a[0],a[p]);
    for(i = 0;i < n;i++){
        cout<<a[i];
    }
}
/**************************************************************
	Problem: 1452
	User: wangyiyang
	Language: C++
	Result: Accepted
	Time:18 ms
	Memory:2076 kb
****************************************************************/