#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000001
	 
int main(){
	
	int n;
	cin>>n;
	
	vector<int> p(n);
	vector<int> pos(n);
	rep(i,n){
		cin>>p[i];
		pos[p[i]] = i;
	}
	
	mint ans = 1;
	int l = pos[0];
	int r = pos[0]+1;
	
	for(int i=1;i<n;i++){
		int t = pos[i];
		if(t<l)l = t;
		else if(t>=r)r = t+1;
		else{
			
			ans *= (r-l-i); 
			
		}
	}
	cout<<ans.val()<<endl;
	
	return 0;
}