import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc =  new Scanner(System.in);
        int n = sc.nextInt();
        if(!sc.hasNextDigit()){
            System.out.print("Invalid input"); return;
        }
        int s=1;
        int a[]=new int[n];
        for(int i=0;i<n;i++){
            a[i]=sc.nextInt();
            s*=a[i];
        }
        System.out.print(s);
    }
}