#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  
  const ll MOD = 998244353;
  
  int N;
  cin >> N;
  
  ll ans = 0;
  map<int, ll> m;
  
  for (int i = 0; i < N; i++) {
    ll A;
    cin >> A;
    
    ll t = (m[A - 1] + 1) % MOD;
    m[A] = (m[A] + t) % MOD;
    ans = (ans + t) % MOD;
  }
  cout << ans - N << '\n';
}