#include <bits/stdc++.h>
#include<atcoder/all>
using namespace atcoder;
using namespace std;
using ll=long long;
using ld=long double;
ld pie=3.141592653589793;
ll mod=998244353;
ll inf=1000000000000000001;//10^17
int main(){
    ll n;
    cin >> n;
    vector<ll>a(n);
    for (ll i = 0; i < n; i++)
    {
        cin >> a[i];
    }
    map<ll,ll>memo;
    ll ans=0;
    for (ll i = 0; i < n; i++)
    {
        ans+=memo[a[i]-1];
        memo[a[i]]+=memo[a[i]-1]+1;
        ans%=mod;
        memo[a[i]]%=mod;
    }
    cout << ans << endl;
}