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];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		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];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		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];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		long [] A = new long [N];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		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 for(int i=0;i<N;i++){A[i] = sc.nextLong();} int i=0; int i=0; i 0 i<N i N i++ i++ i {A[i] = sc.nextLong();} {A[i] = sc.nextLong();} A[i] = sc.nextLong() A[i] A i sc.nextLong() sc.nextLong sc Arrays.sort(A) Arrays.sort Arrays A long ans = 1; ans 1 String str = "1000000000000000000"; str "1000000000000000000" long limit = Long.parseLong(str); limit Long.parseLong(str) Long.parseLong Long str for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        } int i=0; int i=0; i 0 i<N i N i++ i++ i {
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        } {
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        } if(A[i]==0){ans=0;break;} A[i]==0 A[i] A i 0 {ans=0;break;} ans=0 ans 0 break; if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;} A[i]<=limit/ans A[i] A i limit/ans limit ans {ans*=A[i];} ans*=A[i] ans A[i] A i {ans=-1;break;} ans=-1 ans -1 1 break; 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];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		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];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		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];
        for(int i=0;i<N;i++){A[i] = sc.nextLong();}
        Arrays.sort(A);
		long ans = 1;
        String str = "1000000000000000000";
        long limit = Long.parseLong(str);
        for(int i=0;i<N;i++){
          if(A[i]==0){ans=0;break;}
          if(A[i]<=limit/ans){ans*=A[i];}
          else{ans=-1;break;}
        }
		System.out.println(ans);
	}
}