#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cmath>
#include<queue>
#include<vector>
#include<cstring>
#include<string>
#include<cstdlib>
using namespace std;
int a[100010],n,num=0,place[100010];
long long plan=0;
void fun(int x)
{
	if(x==num+1)
	{
		for(int i=2;i<=n;i++)
		{
			if(place[i]<=place[i-1]) return;
		}
		//printf("%d %d %d\n",place[1],place[2],place[3]);
		plan++;
		return;
	}
	for(int i=1;i<=n;i++)
	{
		if(a[i])
		{
		a[i]--;
		if(a[i]==0)  place[i]=x;
//		printf("%d %d %d %d\n",x,place[1],place[2],place[3]);
	    fun(x+1);
	    if(a[i]==0) place[i]=0;
		a[i]++;
	    }
	     else continue;
	}
}
int main()
{
	freopen("asm_formation.in","r",stdin);
	freopen("asm_formation.out","w",stdout);
	cin>>n;
	
	if(n==1)
	{
		if(n==1)
		cout<<"1";
		return 0;
	}
	for(int i=1;i<=n;i++)
	{
		scanf("%d",&a[i]);
	//	cout<<a[i];
		num+=a[i];
	}
	
	fun(1);
	cout<<plan%998244353;
	return 0;
}