atcoder#AGC020B. [AGC020B] Ice Rink Game

[AGC020B] Ice Rink Game

Score : 500500 points

Problem Statement

An adult game master and NN children are playing a game on an ice rink. The game consists of KK rounds. In the ii-th round, the game master announces:

  • Form groups consisting of AiA_i children each!

Then the children who are still in the game form as many groups of AiA_i children as possible. One child may belong to at most one group. Those who are left without a group leave the game. The others proceed to the next round. Note that it's possible that nobody leaves the game in some round.

In the end, after the KK-th round, there are exactly two children left, and they are declared the winners.

You have heard the values of A1A_1, A2A_2, ..., AKA_K. You don't know NN, but you want to estimate it.

Find the smallest and the largest possible number of children in the game before the start, or determine that no valid values of NN exist.

Constraints

  • 1K1051 \leq K \leq 10^5
  • 2Ai1092 \leq A_i \leq 10^9
  • All input values are integers.

Input

Input is given from Standard Input in the following format:

KK

A1A_1 A2A_2 ...... AKA_K

Output

Print two integers representing the smallest and the largest possible value of NN, respectively, or a single integer 1-1 if the described situation is impossible.

4
3 4 3 2
6 8

For example, if the game starts with 66 children, then it proceeds as follows:

  • In the first round, 66 children form 22 groups of 33 children, and nobody leaves the game.
  • In the second round, 66 children form 11 group of 44 children, and 22 children leave the game.
  • In the third round, 44 children form 11 group of 33 children, and 11 child leaves the game.
  • In the fourth round, 33 children form 11 group of 22 children, and 11 child leaves the game.

The last 22 children are declared the winners.

5
3 4 100 3 2
-1

This situation is impossible. In particular, if the game starts with less than 100100 children, everyone leaves after the third round.

10
2 2 2 2 2 2 2 2 2 2
2 3