// #include<bits/stdc++.h>

#include <iostream>

#include <algorithm>

#include <cmath>

#include <string>

#include <cstring>

#include <vector>

using namespace std;

typedef long long LL;

typedef pair<int,int> PII; 

const int N = 1e6+10;

const LL mod = 998244353;

int st[N];

LL fact[N], infact[N];

LL qmi(LL x, LL k)//快速幂

{

    LL res = 1;

    while(k)

    {

        if(k&1)

            res = (LL)res * x %mod;

        k >>= 1;

        x = (LL)x * x % mod;

    }

    return res;

}

void init(int n)

{

    fact[0] = 1, infact[0] = 1;

    for(int i = 1; i <= n; i ++)

    {

        fact[i] = fact[i-1]*i%mod;//n的阶乘

        infact[i] = infact[i-1]*qmi((LL)i, mod-2)%mod;//逆元

    }

    return;

}

LL zuhe(int n, int m)//求组合数

{

    return fact[n] * infact[n-m] %mod* infact[m]%mod;

}

int main(){

    vector<PII> a;

    int n;

    cin >> n;

    init(n);

    int idx = 0;

    for(int i = 0; i < N; i ++) st[i] = -1;

    for(int i = 0; i < n; i ++)

    {

        int x;

        cin >> x;

        if(st[x]>=0)    a[st[x]].second ++;//记录每个数出现了几次

        else

        {

            a.push_back({x, 1});

            st[x] = idx ++;

        }

    }

    sort(a.begin(), a.end());

    int sum = 0;

    LL res = 1;

    for(int i = a.end()-a.begin()-1; i >= 0; i --)sum+=a[i].second;

    //数学公式实现过程

    for(int i = a.end()-a.begin()-1; i >= 0; i --)

    {

        sum -= a[i].second;

        int c = a[i].second;

        if(c >= 2)

            res = res * fact[c]%mod * zuhe((sum + c/2), c/2)%mod;

    }

    cout << res <<endl;

    return 0;

}