题目描述
You are given an integer $x$ represented as a product of $n$ its prime divisors $p_1 \cdot p_2, \cdot \ldots \cdot p_n$. Let $S$ be the set of all positive integer divisors of $x$ (including $1$ and $x$ itself).
We call a set of integers $D$ good if (and only if) there is no pair $a \in D$, $b \in D$ such that $a \ne b$ and $a$ divides $b$.
Find a good subset of $S$ with maximum possible size. Since the answer can be large, print the size of the subset modulo $998244353$.
Input
The first line contains the single integer $n$ ($1 \le n \le 2 \cdot 10^5$) — the number of prime divisors in representation of $x$.
The second line contains $n$ integers $p_1, p_2, \dots, p_n$ ($2 \le p_i \le 3 \cdot 10^6$) — the prime factorization of $x$.
Output
Print the maximum possible size of a good subset modulo $998244353$.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分
样例输入
样例输出
提示
In the first sample, $x = 2999999 \cdot 43 \cdot 2999957$ and one of the maximum good subsets is $\{ 43, 2999957, 2999999 \}$.
In the second sample, $x = 2 \cdot 3 \cdot 2 \cdot 3 \cdot 2 \cdot 2 = 144$ and one of the maximum good subsets is $\{ 9, 12, 16 \}$.