#include <iostream>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <algorithm>

using namespace std;


int main()
{
    int n, mm, nn;
    int a[101];
    int ff[101];
    int i, j;
    int ee, oo, dd;

    while(scanf("%d", &n)!=EOF)
    {
        if(n==1)
        {
            scanf("%d", &nn);
            if(nn%2==0)
              {
                  printf("-1\n");
                  continue;
              }
              else if(nn%2==1 )
              {
                  printf("%d\n", nn);
                  continue;
              }

        }

        ee=0; oo=0; dd=0;
        mm=999999;
         for(i=0; i<n; i++)
         {
             scanf("%d", &a[i] );
             if(a[i]%2==1)
             {
                 oo++; //奇数
                 if( a[i]<mm )
                 {
                   mm=a[i];
                 }
             }
             else if(a[i]%2==0)
             {
                ee++;
                if(a[i]==0)
                  dd++; //0的个数
             }
         }
         if(oo==0)
        {
               printf("-1\n");
               continue;
        }
         if(dd>=n-1)
         {
             printf("-1\n");
               continue;
         }
          memset(ff, 0, sizeof(ff));
         sort(a, a+n);
         for(i=0; i<n; i++)
         {
             if(a[i]==mm)
             {
                ff[i]=1;
                break;
             }
         }
         for(i=n-1; i>=0; i--)
         {
             if(ff[i]==0)
               printf("%d", a[i] );
         }
         printf("%d\n", mm);
    }
    return 0;
}