import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.Scanner;

class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
		int n, e, k=0, m, maxk = 0, maxn = 1000000000, p = 1;
		Scanner in = new Scanner(System.in);
		e = in.nextInt();
		while (e -- > 0) {
        	n = in.nextInt();
			if (p <= n){
				m = n;
				k = 0;
				while ((n % 10) == 0) {
					//считает нули
					n = n / 10;
					k ++;
				}
				if (maxk < k) {
					maxn = m;
					maxk = k;
					p = 1;
					for (int i = 1; i < maxk; i ++) {
						p *= 10;
					}
				} else if (maxk == k) {
					if(maxn > m) maxn = m;
				}
			}
		}
		System.out.print(maxn);
	}
}