Codeforces Beta Round 48
D
Geometrical problem
Codeforces
2200
原题
← CE →
翻译中…

Polycarp loves geometric progressions — he collects them. However, as such progressions occur very rarely, he also loves the sequences of numbers where it is enough to delete a single element to get a geometric progression.

翻译中…

In this task we shall define geometric progressions as finite sequences of numbers $*a*_{1}, *a*_{2}, ..., *a*_{*k*}$, where $*a*_{*i*} = *c*·*b*^{*i* - 1}$ for some real numbers $*c*$ and $*b*$. For example, the sequences [2, -4, 8], [0, 0, 0, 0], [199] are geometric progressions and [0, 1, 2, 3] is not.

翻译中…

Recently Polycarp has found a sequence and he can't classify it. Help him to do it. Determine whether it is a geometric progression. If it is not, check if it can become a geometric progression if an element is deleted from it.

翻译中…

Input

翻译中…

The first line contains an integer $*n*$ ($1 ≤ *n* ≤ 10^{5}$) — the number of elements in the given sequence. The second line contains the given sequence. The numbers are space-separated. All the elements of the given sequence are integers and their absolute value does not exceed $10^{4}$.

翻译中…

Output

翻译中…

Print 0, if the given sequence is a geometric progression. Otherwise, check if it is possible to make the sequence a geometric progression by deleting a single element. If it is possible, print 1. If it is impossible, print 2.

翻译中…

样例

Input #1
4
3 6 12 24
Output #1
0
InputCopy OutputCopy
Input #2
4
-8 -16 24 -32
Output #2
1
InputCopy OutputCopy
Input #3
4
0 1 2 3
Output #3
2
InputCopy OutputCopy
题目信息
题号
51D
时间限制
1 s
内存限制
256 MB
标签
模拟

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。