#ifdef LOCAL
#define _GLIBCXX_DEBUG 1
#endif
#pragma GCC optimize("O3")
// =============================================== CODE ================================================ //
#include <bits/stdc++.h>
#define F first
#define S second
#define pb push_back
#define pob pop_back
#define all(x) begin(x), end(x)
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#ifdef LOCAL
#define HEHE freopen("in.txt", "r", stdin);
#define debug(HEHE...) std::cerr << "\e[1;31m" << #HEHE << "\033[0m" << " = ", dout(HEHE)
void dout() { std::cerr << "\n"; }
template <typename T, typename... U>
void dout(T t, U... u) { std::cerr << t << ' ', dout(u...); }
#else
#define HEHE ios_base::sync_with_stdio(0), cin.tie(0);
#define debug(...) 7122
#endif
using namespace std;

template<typename T1, typename T2>
bool chmin(T1 &a, T2 b) { return a > b ? a = b, 1 : 0; }
template<typename T1, typename T2>
bool chmax(T1 &a, T2 b) { return a < b ? a = b, 1 : 0; }

#define ssize(x) (int)(x.size())
#define int long long

const int mod = 998244353;

void solve() {
    int n;
    cin >> n;
    map<int, int> dp;
    int ans = 0;
    for (int i = 0; i < n; i++) {
        int x; cin >> x;
        ans = (ans + dp[x - 1]) % mod;
        dp[x] = (1 + dp[x - 1] + dp[x]) % mod;
    }
    cout << ans << '\n';
}

signed main() {
    HEHE
    int t = 1; // cin >> t;
    while (t--) solve();
}