#define _USE_MATH_DEFINES #include "bits/stdc++.h" using namespace std; #define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i)) #define rep(i,j) FOR(i,0,j) #define each(x,y) for(auto &(x):(y)) #define mp make_pair #define MT make_tuple #define all(x) (x).begin(),(x).end() #define debug(x) cout<<#x<<": "<<(x)<; using vi = vector; using vll = vector; template class ModInt { public: ModInt() :value(0) {} ModInt(long long val) :value((int)(val < 0 ? MOD + val % MOD : val % MOD)) { } ModInt& operator+=(ModInt that) { value = value + that.value; if (value >= MOD)value -= MOD; return *this; } ModInt& operator-=(ModInt that) { value -= that.value; if (value < 0)value += MOD; return *this; } ModInt& operator*=(ModInt that) { value = (int)((long long)value * that.value % MOD); return *this; } ModInt& operator/=(ModInt that) { return *this *= that.inverse(); } ModInt operator+(ModInt that) const { return ModInt(*this) += that; } ModInt operator-(ModInt that) const { return ModInt(*this) -= that; } ModInt operator*(ModInt that) const { return ModInt(*this) *= that; } ModInt operator/(ModInt that) const { return ModInt(*this) /= that; } ModInt pow(long long k) const { ModInt n = *this, res = 1; if (k < 0) { k = -k; n = n.inverse(); } while (k) { if (k & 1)res *= n; n *= n; k >>= 1; } return res; } ModInt inverse() const { long long a = value, b = MOD, u = 1, v = 0; while (b) { long long t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v); } return ModInt(u); } int toi() const { return value; } private: int value; }; typedef ModInt<998244353> mint; ostream& operator<<(ostream & os, const mint & x) { os << x.toi(); return os; } template vector compress(vector &v) { vector a = v; sort(all(a)); a.erase(unique(all(a)), a.end()); each(b, v)b = (int)(lower_bound(all(a), b) - a.begin()); return a; } template struct BinaryIndexedTree { int n; vector t; BinaryIndexedTree() {} BinaryIndexedTree(int _n) :n(_n + 1), t(_n + 1) {} void add(int k, Val val) { k++; while (k < n) { t[k] += val; k += (k & -k); } } void set(int k, Val val) { add(k, -sum(k, k + 1)); add(k, val); } Val sum(int k) { Val r = 0; while (k > 0) { r += t[k]; k -= (k & -k); } return r; } Val sum(int l, int r) { return sum(r) - sum(l); } }; typedef BinaryIndexedTree BIT; void solve() { int N; cin >> N; vi A(N); rep(i, N) { cin >> A[i]; } // A[i] => B[A[i]] auto B = compress(A); int M = sz(B); // M<=N BIT f[3], g[3]; rep(i, 3) { f[i] = g[i] = BIT(M); } rep(j, N) { int k = A[j], a = B[k]; rep(i, 2) { f[i + 1].add(k, f[i].sum(k + 1, M) + g[i].sum(k + 1, M) * a); g[i + 1].add(k, g[i].sum(k + 1, M)); } f[0].add(k, a); g[0].add(k, 1); } cout << f[2].sum(M) << endl; } int main() { ios::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(15); solve(); return 0; }