import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	}
} import java.util.*; util.* java public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	}
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc long[] a = new long[n]; a new long[n] n long ans = 1; ans 1 long max = (long)Math.pow(10,18); max (long)Math.pow(10,18) Math.pow Math 10 18 for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		} int i=0; int i=0; i 0 i<n i n i++ i++ i {
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		} {
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		} a[i]=sc.nextLong() a[i] a i sc.nextLong() sc.nextLong sc if(a[i]==0){
		        System.out.println(0);
		        return;
		    } a[i]==0 a[i] a i 0 {
		        System.out.println(0);
		        return;
		    } System.out.println(0) System.out.println System.out System System.out 0 return; if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		} ans != 0 ans 0 {
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		} for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    } int i=0; int i=0; i 0 i<n i n i++ i++ i {
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    } {
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    } if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        } max/ans <a[i] max/ans max ans a[i] a i {
		            System.out.println(-1);
		            return;
		        } System.out.println(-1) System.out.println System.out System System.out -1 1 return; {
		            ans = ans*a[i];
		        } ans = ans*a[i] ans ans*a[i] ans a[i] a i System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	}
} public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	}
} Main
import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		long[] a = new long[n];
		long ans = 1;
		long max = (long)Math.pow(10,18);
		
		for(int i=0; i<n; i++){
		    a[i]=sc.nextLong();
		    if(a[i]==0){
		        System.out.println(0);
		        return;
		    }
		}
		
		if(ans != 0){
		    for(int i=0; i<n; i++){
		        if(max/ans <a[i]){
		            System.out.println(-1);
		            return;
		        }else{
		            ans = ans*a[i];
		        }
		    }
		}
		
		System.out.println(ans);
	}
}
