import java.util.*;
import java.io.*;
import java.math.*;
public class Main{
  //↓見なくていいよ！ここから------------------------------------------
  static public class InputIterator{
    ArrayList<String> inputLine = new ArrayList<String>(1024);
    int index = 0; int max;
    InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    }
    public boolean hasNext(){return (index < max);}
    public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    }
  }
  
  static InputIterator ii = new InputIterator();//リアクティブでは使えないので諦めてScanner使うこと
  static PrintWriter out = new PrintWriter(System.out);
  static void flush(){out.flush();}
  static void myout(Object t){out.println(t);}
  static void myerr(Object t){System.err.println(t);}
  static String next(){return ii.next();}
  static int nextInt(){return Integer.parseInt(next());}
  static long nextLong(){return Long.parseLong(next());}
  static ArrayList<String> nextStrArray(){return myHanSpSplit(next());}
  static ArrayList<String> myHanSpSplit(String str){return new ArrayList<String>(Arrays.asList(str.split(" ")));}
  static ArrayList<String> nextCharArray(){return mySingleSplit(next());}
  static ArrayList<String> mySingleSplit(String str){return new ArrayList<String>(Arrays.asList(str.split("")));}
  static ArrayList<Integer> nextIntArray(){
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  }
  static ArrayList<Long> nextLongArray(){
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  }
  static String kaigyoToStr(String[] list){return String.join("\n",list);}
  static String kaigyoToStr(ArrayList<String> list){return String.join("\n",list);}
  static String hanSpToStr(String[] list){return String.join(" ",list);}
  static String hanSpToStr(ArrayList<String> list){return String.join(" ",list);}
  public static void main(String[] args){
    solve();
    flush();
  }
  //↑見なくていいよ！ここまで------------------------------------------
  static public void solve(){//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  }
  //Method addition frame start

  //Method addition frame end
} import java.util.*; util.* java import java.io.*; io.* java import java.math.*; math.* java public class Main{
  //↓見なくていいよ！ここから------------------------------------------
  static public class InputIterator{
    ArrayList<String> inputLine = new ArrayList<String>(1024);
    int index = 0; int max;
    InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    }
    public boolean hasNext(){return (index < max);}
    public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    }
  }
  
  static InputIterator ii = new InputIterator();//リアクティブでは使えないので諦めてScanner使うこと
  static PrintWriter out = new PrintWriter(System.out);
  static void flush(){out.flush();}
  static void myout(Object t){out.println(t);}
  static void myerr(Object t){System.err.println(t);}
  static String next(){return ii.next();}
  static int nextInt(){return Integer.parseInt(next());}
  static long nextLong(){return Long.parseLong(next());}
  static ArrayList<String> nextStrArray(){return myHanSpSplit(next());}
  static ArrayList<String> myHanSpSplit(String str){return new ArrayList<String>(Arrays.asList(str.split(" ")));}
  static ArrayList<String> nextCharArray(){return mySingleSplit(next());}
  static ArrayList<String> mySingleSplit(String str){return new ArrayList<String>(Arrays.asList(str.split("")));}
  static ArrayList<Integer> nextIntArray(){
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  }
  static ArrayList<Long> nextLongArray(){
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  }
  static String kaigyoToStr(String[] list){return String.join("\n",list);}
  static String kaigyoToStr(ArrayList<String> list){return String.join("\n",list);}
  static String hanSpToStr(String[] list){return String.join(" ",list);}
  static String hanSpToStr(ArrayList<String> list){return String.join(" ",list);}
  public static void main(String[] args){
    solve();
    flush();
  }
  //↑見なくていいよ！ここまで------------------------------------------
  static public void solve(){//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  }
  //Method addition frame start

  //Method addition frame end
} Main static InputIterator ii = new InputIterator();//リアクティブでは使えないので諦めてScanner使うこと ii new InputIterator() static PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) static void flush(){out.flush();} flush {out.flush();} out.flush() out.flush out static void myout(Object t){out.println(t);} myout {out.println(t);} out.println(t) out.println out t Object t t static void myerr(Object t){System.err.println(t);} myerr {System.err.println(t);} System.err.println(t) System.err.println System.err System System.err t Object t t static String next(){return ii.next();} next {return ii.next();} return ii.next(); ii.next() ii.next ii static int nextInt(){return Integer.parseInt(next());} nextInt {return Integer.parseInt(next());} return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next static long nextLong(){return Long.parseLong(next());} nextLong {return Long.parseLong(next());} return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next static ArrayList<String> nextStrArray(){return myHanSpSplit(next());} nextStrArray {return myHanSpSplit(next());} return myHanSpSplit(next()); myHanSpSplit(next()) myHanSpSplit next() next static ArrayList<String> myHanSpSplit(String str){return new ArrayList<String>(Arrays.asList(str.split(" ")));} myHanSpSplit {return new ArrayList<String>(Arrays.asList(str.split(" ")));} return new ArrayList<String>(Arrays.asList(str.split(" "))); new ArrayList<String>(Arrays.asList(str.split(" "))) String str str static ArrayList<String> nextCharArray(){return mySingleSplit(next());} nextCharArray {return mySingleSplit(next());} return mySingleSplit(next()); mySingleSplit(next()) mySingleSplit next() next static ArrayList<String> mySingleSplit(String str){return new ArrayList<String>(Arrays.asList(str.split("")));} mySingleSplit {return new ArrayList<String>(Arrays.asList(str.split("")));} return new ArrayList<String>(Arrays.asList(str.split(""))); new ArrayList<String>(Arrays.asList(str.split(""))) String str str static ArrayList<Integer> nextIntArray(){
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  } nextIntArray {
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  } ArrayList<Integer> ret = new ArrayList<Integer>(); ret new ArrayList<Integer>() ArrayList<String> input = nextStrArray(); input nextStrArray() nextStrArray for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    } int i = 0; int i = 0; i 0 i < input.size() i input.size() input.size input i++ i++ i {
      ret.add(Integer.parseInt(input.get(i)));
    } {
      ret.add(Integer.parseInt(input.get(i)));
    } ret.add(Integer.parseInt(input.get(i))) ret.add ret Integer.parseInt(input.get(i)) Integer.parseInt Integer input.get(i) input.get input i return ret; ret static ArrayList<Long> nextLongArray(){
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  } nextLongArray {
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  } ArrayList<Long> ret = new ArrayList<Long>(); ret new ArrayList<Long>() ArrayList<String> input = nextStrArray(); input nextStrArray() nextStrArray for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    } int i = 0; int i = 0; i 0 i < input.size() i input.size() input.size input i++ i++ i {
      ret.add(Long.parseLong(input.get(i)));
    } {
      ret.add(Long.parseLong(input.get(i)));
    } ret.add(Long.parseLong(input.get(i))) ret.add ret Long.parseLong(input.get(i)) Long.parseLong Long input.get(i) input.get input i return ret; ret static String kaigyoToStr(String[] list){return String.join("\n",list);} kaigyoToStr {return String.join("\n",list);} return String.join("\n",list); String.join("\n",list) String.join String "\n" list String[] list list static String kaigyoToStr(ArrayList<String> list){return String.join("\n",list);} kaigyoToStr {return String.join("\n",list);} return String.join("\n",list); String.join("\n",list) String.join String "\n" list ArrayList<String> list list static String hanSpToStr(String[] list){return String.join(" ",list);} hanSpToStr {return String.join(" ",list);} return String.join(" ",list); String.join(" ",list) String.join String " " list String[] list list static String hanSpToStr(ArrayList<String> list){return String.join(" ",list);} hanSpToStr {return String.join(" ",list);} return String.join(" ",list); String.join(" ",list) String.join String " " list ArrayList<String> list list public static void main(String[] args){
    solve();
    flush();
  } main {
    solve();
    flush();
  } solve() solve flush() flush String[] args args //↑見なくていいよ！ここまで------------------------------------------
  static public void solve(){//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  } solve {//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  } int N = nextInt(); N nextInt() nextInt ArrayList<String> list = nextStrArray(); list nextStrArray() nextStrArray BigInteger output = new BigInteger("1"); output new BigInteger("1") for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    } int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    } {
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    } if(list.get(i).equals("0")){
        myout(0);
        return;
      } list.get(i).equals("0") list.get(i).equals list.get(i) list.get list i "0" {
        myout(0);
        return;
      } myout(0) myout 0 return; BigInteger max = new BigInteger("1000000000000000000"); max new BigInteger("1000000000000000000") for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    } int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    } {
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    } output = output.multiply(new BigInteger(list.get(i))) output output.multiply(new BigInteger(list.get(i))) output.multiply output new BigInteger(list.get(i)) if(output.compareTo(max) == 1){
        myout(-1);
        return;
      } output.compareTo(max) == 1 output.compareTo(max) output.compareTo output max 1 {
        myout(-1);
        return;
      } myout(-1) myout -1 1 return; myout(output.toString()) myout output.toString() output.toString output static public class InputIterator{
    ArrayList<String> inputLine = new ArrayList<String>(1024);
    int index = 0; int max;
    InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    }
    public boolean hasNext(){return (index < max);}
    public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    }
  } InputIterator ArrayList<String> inputLine = new ArrayList<String>(1024); inputLine new ArrayList<String>(1024) int index = 0; index 0 int max; max InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    } InputIterator {
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    } BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      } true {
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      } String read; read try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        } catch(IOException e){
          read = null;
        } IOException e {
          read = null;
        } read = null read null {
          read = br.readLine();
        } read = br.readLine() read br.readLine() br.readLine br if(read != null){
          inputLine.add(read);
        }else{
          break;
        } read != null read null {
          inputLine.add(read);
        } inputLine.add(read) inputLine.add inputLine read {
          break;
        } break; max = inputLine.size() max inputLine.size() inputLine.size inputLine public boolean hasNext(){return (index < max);} hasNext {return (index < max);} return (index < max); (index < max) index max public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    } next {
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    } if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      } hasNext() hasNext {
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      } String returnStr = inputLine.get(index); returnStr inputLine.get(index) inputLine.get inputLine index index++ index return returnStr; returnStr {
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      } throw new IndexOutOfBoundsException("これ以上入力はないよ。"); new IndexOutOfBoundsException("これ以上入力はないよ。") public class Main{
  //↓見なくていいよ！ここから------------------------------------------
  static public class InputIterator{
    ArrayList<String> inputLine = new ArrayList<String>(1024);
    int index = 0; int max;
    InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    }
    public boolean hasNext(){return (index < max);}
    public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    }
  }
  
  static InputIterator ii = new InputIterator();//リアクティブでは使えないので諦めてScanner使うこと
  static PrintWriter out = new PrintWriter(System.out);
  static void flush(){out.flush();}
  static void myout(Object t){out.println(t);}
  static void myerr(Object t){System.err.println(t);}
  static String next(){return ii.next();}
  static int nextInt(){return Integer.parseInt(next());}
  static long nextLong(){return Long.parseLong(next());}
  static ArrayList<String> nextStrArray(){return myHanSpSplit(next());}
  static ArrayList<String> myHanSpSplit(String str){return new ArrayList<String>(Arrays.asList(str.split(" ")));}
  static ArrayList<String> nextCharArray(){return mySingleSplit(next());}
  static ArrayList<String> mySingleSplit(String str){return new ArrayList<String>(Arrays.asList(str.split("")));}
  static ArrayList<Integer> nextIntArray(){
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  }
  static ArrayList<Long> nextLongArray(){
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  }
  static String kaigyoToStr(String[] list){return String.join("\n",list);}
  static String kaigyoToStr(ArrayList<String> list){return String.join("\n",list);}
  static String hanSpToStr(String[] list){return String.join(" ",list);}
  static String hanSpToStr(ArrayList<String> list){return String.join(" ",list);}
  public static void main(String[] args){
    solve();
    flush();
  }
  //↑見なくていいよ！ここまで------------------------------------------
  static public void solve(){//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  }
  //Method addition frame start

  //Method addition frame end
} public class Main{
  //↓見なくていいよ！ここから------------------------------------------
  static public class InputIterator{
    ArrayList<String> inputLine = new ArrayList<String>(1024);
    int index = 0; int max;
    InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    }
    public boolean hasNext(){return (index < max);}
    public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    }
  }
  
  static InputIterator ii = new InputIterator();//リアクティブでは使えないので諦めてScanner使うこと
  static PrintWriter out = new PrintWriter(System.out);
  static void flush(){out.flush();}
  static void myout(Object t){out.println(t);}
  static void myerr(Object t){System.err.println(t);}
  static String next(){return ii.next();}
  static int nextInt(){return Integer.parseInt(next());}
  static long nextLong(){return Long.parseLong(next());}
  static ArrayList<String> nextStrArray(){return myHanSpSplit(next());}
  static ArrayList<String> myHanSpSplit(String str){return new ArrayList<String>(Arrays.asList(str.split(" ")));}
  static ArrayList<String> nextCharArray(){return mySingleSplit(next());}
  static ArrayList<String> mySingleSplit(String str){return new ArrayList<String>(Arrays.asList(str.split("")));}
  static ArrayList<Integer> nextIntArray(){
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  }
  static ArrayList<Long> nextLongArray(){
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  }
  static String kaigyoToStr(String[] list){return String.join("\n",list);}
  static String kaigyoToStr(ArrayList<String> list){return String.join("\n",list);}
  static String hanSpToStr(String[] list){return String.join(" ",list);}
  static String hanSpToStr(ArrayList<String> list){return String.join(" ",list);}
  public static void main(String[] args){
    solve();
    flush();
  }
  //↑見なくていいよ！ここまで------------------------------------------
  static public void solve(){//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  }
  //Method addition frame start

  //Method addition frame end
} Main
import java.util.*;
import java.io.*;
import java.math.*;
public class Main{
  //↓見なくていいよ！ここから------------------------------------------
  static public class InputIterator{
    ArrayList<String> inputLine = new ArrayList<String>(1024);
    int index = 0; int max;
    InputIterator(){
      BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
      while(true){
        String read;
        try{
          read = br.readLine();
        }catch(IOException e){
          read = null;
        }
        if(read != null){
          inputLine.add(read);
        }else{
          break;
        }
      }
      max = inputLine.size();
    }
    public boolean hasNext(){return (index < max);}
    public String next(){
      if(hasNext()){
        String returnStr = inputLine.get(index);
        index++;
        return returnStr;
      }else{
        throw new IndexOutOfBoundsException("これ以上入力はないよ。");
      }
    }
  }
  
  static InputIterator ii = new InputIterator();//リアクティブでは使えないので諦めてScanner使うこと
  static PrintWriter out = new PrintWriter(System.out);
  static void flush(){out.flush();}
  static void myout(Object t){out.println(t);}
  static void myerr(Object t){System.err.println(t);}
  static String next(){return ii.next();}
  static int nextInt(){return Integer.parseInt(next());}
  static long nextLong(){return Long.parseLong(next());}
  static ArrayList<String> nextStrArray(){return myHanSpSplit(next());}
  static ArrayList<String> myHanSpSplit(String str){return new ArrayList<String>(Arrays.asList(str.split(" ")));}
  static ArrayList<String> nextCharArray(){return mySingleSplit(next());}
  static ArrayList<String> mySingleSplit(String str){return new ArrayList<String>(Arrays.asList(str.split("")));}
  static ArrayList<Integer> nextIntArray(){
    ArrayList<Integer> ret = new ArrayList<Integer>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Integer.parseInt(input.get(i)));
    }
    return ret;
  }
  static ArrayList<Long> nextLongArray(){
    ArrayList<Long> ret = new ArrayList<Long>();
    ArrayList<String> input = nextStrArray();
    for(int i = 0; i < input.size(); i++){
      ret.add(Long.parseLong(input.get(i)));
    }
    return ret;
  }
  static String kaigyoToStr(String[] list){return String.join("\n",list);}
  static String kaigyoToStr(ArrayList<String> list){return String.join("\n",list);}
  static String hanSpToStr(String[] list){return String.join(" ",list);}
  static String hanSpToStr(ArrayList<String> list){return String.join(" ",list);}
  public static void main(String[] args){
    solve();
    flush();
  }
  //↑見なくていいよ！ここまで------------------------------------------
  static public void solve(){//ここがメイン関数代わり
    int N = nextInt();
    ArrayList<String> list = nextStrArray();
    BigInteger output = new BigInteger("1");
    for(int i = 0; i < N; i++){
      if(list.get(i).equals("0")){
        myout(0);
        return;
      }
    }
    BigInteger max = new BigInteger("1000000000000000000");
    for(int i = 0; i < N; i++){
      output = output.multiply(new BigInteger(list.get(i)));
      if(output.compareTo(max) == 1){
        myout(-1);
        return;
      }
    }
    myout(output.toString());
  }
  //Method addition frame start

  //Method addition frame end
}
