/********include********/

#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#include <utility>
#include <functional>
#define popcount __builtin_popcount
using namespace std;

/***/
//#include <iomanip>
//#include <cmath>
#include <bits/stdc++.h>

/********define********/

#define rep(i,x) for(long long i=0;i<x;i++)
#define repn(i,x) for(long long i=1;i<=x;i++)
#define rrep(i,x) for(long long i=x-1;i>=0;i--)
#define rrepn(i,x) for(long long i=x;i>1;i--)
#define REP(i,n,x) for(long long i=n;i<x;i++)
#define REPN(i,n,x) for(long long i=n+1;i<x;i++)

#define pr printf
#define re return
#define mod 1000000007
//#define mod 998244353
#define INF 1e18+5//19桁
const double PI=3.14159265358979323846;
#define fi first
#define se second
#define MAX(a,b) (((a)>(b))?(a):(b))
#define MIN(a,b) (((a)<(b))?(a):(b))

typedef long long int ll;
typedef pair<long long, long long> P;


/********よく使う関数********/

// 素因数分解
vector<pair<long long, long long> > prime_factorize(long long n) {
    vector<pair<long long, long long> > res;
    for (long long p = 2; p * p <= n; ++p) {
        if (n % p != 0) continue;
        int num = 0;
        while (n % p == 0) { ++num; n /= p; }
        res.push_back(make_pair(p, num));
    }
    if (n != 1) res.push_back(make_pair(n, 1));
    return res;
}

// 約数列挙
vector<long long> calc_divisor(long long n) {
    vector<long long> res;
    for (long long i = 1LL; i*i <= n; ++i) {
        if (n % i == 0) {
            res.push_back(i);
            long long j = n / i;
            if (j != i) res.push_back(j);
        }
    }
    sort(res.begin(), res.end());
    return res;
}

//最大公約数
ll gcd(ll x, ll y) { return y ? gcd(y, x % y) : x; }

//最大公約数 複数個
ll gcd(const vector<ll> &v) {
	ll ret = v[0];
	for (ll i = 1; i < v.size(); i++)
		ret = gcd(ret, v[i]);
	return ret;
}

//最小公倍数
ll lcm(ll x, ll y) { return x / gcd(x, y) * y; }

//最小公倍数 複数個
ll lcm(const vector<ll> &v) {
	ll ret = v[0];
	for (ll i = 1; i < v.size(); i++)
		ret = lcm(ret, v[i]);
	return ret;
}

/********変数宣言********/
//vector<long long> g[200020];
vector<pair<long long,long long>> g[200020];
ll s[200020];
bool used[200020];
//bool dp[100005];

ll A,B,C,D,H,K,M,N,Q,R,S,T,W,X,Y;
double dA,dB,dC,dH,dK,dM,dN,dQ,dR,dS,dT,dW,dX,dY;

using i64 = std::int_fast64_t;


std::ostream &operator<<(std::ostream &dest, __int128_t value) {
  std::ostream::sentry s(dest);
  if (s) {
    __uint128_t tmp = value < 0 ? -value : value;
    char buffer[128];
    char *d = std::end(buffer);
    do {
      --d;
      *d = "0123456789"[tmp % 10];
      tmp /= 10;
    } while (tmp != 0);
    if (value < 0) {
      --d;
      *d = '-';
    }
    int len = std::end(buffer) - d;
    if (dest.rdbuf()->sputn(d, len) != len) {
      dest.setstate(std::ios_base::badbit);
    }
  }
  return dest;
}

__int128 parse(string &s) {
  __int128 ret = 0;
  for (int i = 0; i < s.length(); i++)
    if ('0' <= s[i] && s[i] <= '9')
      ret = 10 * ret + s[i] - '0';
  return ret;
}

int main()
{
	cin.tie(0);
    ios::sync_with_stdio(false);
    
    /******初期化***********/
    __int128  ans = 1;
	cin >> N;
    vector<i64>v(N);
    rep(i,N){
        cin>>v[i];
        if(v[i]==0){
            puts("0");
            re 0;

        }
    }
    rep(i,N){
        ans*=v[i];
        if(ans>1000000000000000000){
            puts("-1");
            re 0;
        }
    }
    //cout << 1e18;
    cout << ans;

    re 0;
    
}


Measured memory_bytes: 8748