题目描述
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.
Input
The input is given from Standard Input in the following format:
N
$A_1 A_2 \dots A_N$
Output
Print the answer.
Constraints
- $2 \leq N \leq 2 \times 10^5$
- $0 \leq A_i \leq 10^9$
- All values in the input are integers.
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
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分