import java util Scanner import java lang Math public class MaxNum pub

import java.util.Scanner;
import java.lang.Math;

public class MaxNum {
    public static void main (String[] args) {
        Scanner sc = new Scanner(System.in);
        int size=sc.nextInt(),i,j,k,temp,a,b,c;
        int [] NumbMas=new int [size];
        int [] raz=new int [size];
        for (i=0;i<size;i++)
        {
            NumbMas[i]=sc.nextInt();
            temp=NumbMas[i];
            while(temp>0)
            {
                temp=temp/10;
                raz[i]++;
            }
        }
        for (i=size-1;i>0;i--)
        {
            for (j=0;j<i;j++)
            {
                for (k=0;k<=raz[j] & k<=raz[j+1];k++)
                {
                    a=(int)(NumbMas[j]/Math.pow(10,raz[j]-(k+1)))%10;
                    b=(int)(NumbMas[j+1]/Math.pow(10,raz[j+1]-(k+1)))%10;

                    if ((k==raz[j] | k==raz[j+1] )) {
                        if (raz[j] == 1 & (a < b)) {
                            temp = NumbMas[j];
                            NumbMas[j] = NumbMas[j + 1];
                            NumbMas[j + 1] = temp;
                            temp = raz[j];
                            raz[j] = raz[j + 1];
                            raz[j + 1] = temp;
                            break;
                        } else if (raz[j] > raz[j + 1]) {
                            for (c = 1; c <= (raz[j] - raz[j + 1]); c++) {
                                if ((int) (NumbMas[j] / Math.pow(10, raz[j] - (c))) % 10 < (int) (NumbMas[j] / Math.pow(10, (raz[j] - raz[j + 1]) - c)) % 10)
                                    break;
                                else {
                                    temp = NumbMas[j];
                                    NumbMas[j] = NumbMas[j + 1];
                                    NumbMas[j + 1] = temp;
                                    temp = raz[j];
                                    raz[j] = raz[j + 1];
                                    raz[j + 1] = temp;
                                    break;
                                }
                            }
                        } else if (raz[j + 1] > raz[j]) {
                            for (c = 1; c <= (raz[j + 1] - raz[j]); c++) {
                                if ((int) (NumbMas[j + 1] / Math.pow(10, raz[j + 1] - (c))) % 10 > (int) (NumbMas[j + 1] / Math.pow(10, (raz[j + 1] - raz[j]) - c)) % 10)
                                    break;
                                else {
                                    temp = NumbMas[j];
                                    NumbMas[j] = NumbMas[j + 1];
                                    NumbMas[j + 1] = temp;
                                    temp = raz[j];
                                    raz[j] = raz[j + 1];
                                    raz[j + 1] = temp;
                                    break;
                                }
                            }
                        }
                    }

                    if(a<b & !(k==raz[j] | k==raz[j+1]))
                    {
                        temp=NumbMas[j];
                        NumbMas[j]=NumbMas[j+1];
                        NumbMas[j+1]=temp;
                        temp=raz[j];
                        raz[j]=raz[j+1];
                        raz[j+1]=temp;
                        break;
                    }

                    if (a>b)
                        break;
                }
            }
        }
        for (i=0;i<size-1;i++)
        {
            if (NumbMas[i]==0)
            {
                temp=NumbMas[i];
                NumbMas[i]=NumbMas[i+1];
                NumbMas[i+1]=temp;
                temp=raz[i];
                raz[i]=raz[i+1];
                raz[i+1]=temp;
            }
        }
        for (i=0;i<size;i++)
        {
            System.out.print(NumbMas[i]);
        }
    }
}