#include<iostream>
using namespace std;
int main()
{
	int a[100],n,i,j,aux;
	cout<<"n="; cin>>n;
	for(i=1;i<=n;i++) cin>>a[i];
	for(i=1;i<=n;i++)
		for(j=i+1;j<=n;j++) 
			if(a[i]>a[j])
			{
				aux=a[i];
				a[i]=a[j];
				a[j]=aux;
			}
	if(a[1]==0)
	{
		i=2;
		while(a[i]==0) i++;
		a[1]=a[i];
		a[i]=0;
	}		
	for(i=1;i<=n;i++) cout<<a[i];
	return 0;
}