#include <iostream>

using namespace std;

int main()
{
    int n, prod = 1, ex2 = 0, ex5 = 0, x;
    cin >> n;
    for(int i = 1; i <= n; i++)
    {
        cin >> x;
        while(x % 2 == 0)
        {
            x /= 2;
            ex2++;
        }
        while(x % 5 ==0)
        {
            x /= 5;
            ex5++;
        }
        prod = prod * (x % 10) % 10;
    }
    if(ex5 > ex2)
        cout << '5';
    else
    {
        for(int i = 1; i <= ex2 - ex5; i++)
            prod = prod * 2 % 10;
        cout << prod;
    }
    return 0;
}