201480: [AtCoder]ARC148 A - mod M

Problem Statement

You are given a sequence $A = (A_1, A_2, ..., A_N)$.
You may perform the following operation exactly once.

• Choose an integer $M$ at least $2$. Then, for every integer $i$ ($1 \leq i \leq N$), replace $A_i$ with the remainder when $A_i$ is divided by $M$.

For instance, if $M = 4$ is chosen when $A = (2, 7, 4)$, $A$ becomes $(2 \bmod 4, 7 \bmod 4, 4 \bmod 4) = (2, 3, 0)$.

Find the minimum possible number of different elements in $A$ after the operation.

Constraints

• $2 \leq N \leq 2 \times 10^5$
• $0 \leq A_i \leq 10^9$
• All values in the input are integers.

Input

The input is given from Standard Input in the following format:

$N$
$A_1$ $A_2$ $\dots$ $A_N$

Output

Print the answer.

Sample Input 1

3
1 4 8

Sample Output 1

2

If you choose $M = 3$, you will have $A = (1 \bmod 3, 4 \bmod 3, 8 \bmod 3) = (1, 1, 2)$, where $A$ contains two different elements.
The number of different elements in $A$ cannot become $1$, so the answer is $2$.

Sample Input 2

4
5 10 15 20

Sample Output 2

1

If you choose $M = 5$, you will have $A = (0, 0, 0, 0)$, which is optimal.

Sample Input 3

10
3785 5176 10740 7744 3999 3143 9028 2822 4748 6888

Sample Output 3

1