/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author Gosu_Hiroo
 */

#include <iostream>
#include <fstream>

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
#define tr(container, it) \
        for (auto it = container.begin(); it != container.end(); it++)
#define scontains(c, x) ((c).find(x) != (c).end())   //O(log n)
#define contains(c, x) (find((c).begin(),(c).end(),x) != (c).end()) //O(n)
#define pll pair<ll,ll>
#define pii pair<int,int>
#define mll map<ll,ll>
#define intv(x, a, b)((x)>=a && (x)<=b)
#define  rep(i, _begin, _end) for (__typeof(_end) end = _end, begin = _begin,  i = (begin) - ((begin) > (end)); i != (end) - ((begin) > (end)); i += 1 - 2 * ((begin) > (end)))
#define  _for(i, end) for (__typeof(end) i = 0, _len = (end); i < (_len); i += 1)
#define all(x) (x).begin(),(x).end()
#define SZ(x) ((int)(x).size())
#define F first
#define S second
#define y0 y3487465
#define y1 y8687969
#define j0 j1347829
#define j1 j234892
#define what_is(x) cerr << #x << " is " << x << endl;
#define error(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }
#define mod(x, m) ((((x) % (m)) + (m)) % (m))
#define bit(n) (1LL<<(n))
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );
#define readint ({int t;cin >> t;t;})
const double PI = 2 * acos(.0);
const int INF = 0x3f3f3f3f;
const ll LLINF = 1000000000000000005LL;;
const ll MOD = (ll) (1e9) + 7;

void _mod(ll &x) { x = mod(x, MOD); }

//const ll MOD = (ll) 998244353 ;
const double EPS = 1e-10;
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

void err(istream_iterator<string> it) {}

template<typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
    cerr << *it << " = " << a << endl;
    err(++it, args...);
}

template<typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val) {
    std::fill((T *) array, (T *) (array + N), val);
}

template<typename T>
ostream &operator<<(ostream &os, const vector<T> V) {
    for (auto v : V)os << v << " ";
    return os;
}

template<typename T>
ostream &operator<<(ostream &os, const set<T> V) {
    for (auto v : V)os << v << " ";
    return os;
}

template<class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}

template<class T>
bool chmin(T &a, const T &b) {
    if (b < a) {
        a = b;
        return 1;
    }
    return 0;
}

//#define int ll

class BIceRinkGame {
public:
    ll A[101010];

    void solve(std::istream &cin, std::ostream &cout) {
        int N;
        cin >> N;
        _for(i, N)cin >> A[i];
        ll mi = 2, mx = 2;
        rep(i, N, 0) {
            if(mi / A[i] == mx / A[i] && mi % A[i] !=0 && mx % A[i] != 0){
                cout << -1 << endl;
                return;
            }
            mi = (mi + A[i] - 1) / A[i] * A[i];
            if (mx < A[i]) {
                cout << -1 << endl;
                return;
            }
            mx = (mx / A[i] + 1) * A[i] - 1;
            if( mi > mx){
                cout << -1 << endl;
                return;
            }
        }
        cout << mi << " " << mx << endl;


    }


};


#undef int
int main() {


	BIceRinkGame solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	in.tie(0); ios::sync_with_stdio(0); out<<fixed<<setprecision(20);
	solver.solve(in, out);
	return 0;
}


Measured memory_bytes: 1024