#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class t, class u>
void chmax(t& first, u second) {
  if (first < second) first = second;
}
template <class t, class u>
void chmin(t& first, u second) {
  if (second < first) first = second;
}
template <class t>
using vc = vector<t>;
template <class t>
using vvc = vc<vc<t>>;
using pi = pair<ll, ll>;
using vi = vc<ll>;
template <class t, class u>
ostream& operator<<(ostream& os, const pair<t, u>& p) {
  return os << "{" << p.first << "," << p.second << "}";
}
template <class t>
ostream& operator<<(ostream& os, const vc<t>& v) {
  os << "{";
  for (auto e : v) os << e << ",";
  return os << "}";
}
using uint = unsigned;
using ull = unsigned long long;
template <class t, size_t n>
ostream& operator<<(ostream& os, const array<t, n>& first) {
  return os << vc<t>(first.begin(), first.end());
}
template <ll i, class T>
void print_tuple(ostream&, const T&) {}
template <ll i, class T, class H, class... Args>
void print_tuple(ostream& os, const T& t) {
  if (i) os << ",";
  os << get<i>(t);
  print_tuple<i + 1, T, Args...>(os, t);
}
template <class... Args>
ostream& operator<<(ostream& os, const tuple<Args...>& t) {
  os << "{";
  print_tuple<0, tuple<Args...>, Args...>(os, t);
  return os << "}";
}
template <class t>
void print(t x, ll suc = 1) {
  cout << x;
  if (suc == 1) cout << "\n";
  if (suc == 2) cout << " ";
}
ll read() {
  ll i;
  cin >> i;
  return i;
}
vi readvi(ll n, ll off = 0) {
  vi v(n);
  for (ll i = ll(0); i < ll(n); i++) v[i] = read() + off;
  return v;
}
template <class T>
void print(const vector<T>& v, ll suc = 1) {
  for (ll i = ll(0); i < ll(v.size()); i++)
    print(v[i], i == ll(v.size()) - 1 ? suc : 2);
}
string readString() {
  string s;
  cin >> s;
  return s;
}
template <class T>
T sq(const T& t) {
  return t * t;
}
void yes(bool ex = true) {
  cout << "Yes"
       << "\n";
  if (ex) exit(0);
}
void no(bool ex = true) {
  cout << "No"
       << "\n";
  if (ex) exit(0);
}
void possible(bool ex = true) {
  cout << "Possible"
       << "\n";
  if (ex) exit(0);
}
void impossible(bool ex = true) {
  cout << "Impossible"
       << "\n";
  if (ex) exit(0);
}
constexpr ll ten(ll n) { return n == 0 ? 1 : ten(n - 1) * 10; }
const ll infLL = LLONG_MAX / 3;
const ll inf = infLL;
ll topbit(signed t) { return t == 0 ? -1 : 31 - __builtin_clz(t); }
ll topbit(ll t) { return t == 0 ? -1 : 63 - __builtin_clzll(t); }
ll botbit(signed first) { return first == 0 ? 32 : __builtin_ctz(first); }
ll botbit(ll first) { return first == 0 ? 64 : __builtin_ctzll(first); }
ll popcount(signed t) { return __builtin_popcount(t); }
ll popcount(ll t) { return __builtin_popcountll(t); }
bool ispow2(ll i) { return i && (i & -i) == i; }
ll mask(ll i) { return (ll(1) << i) - 1; }
bool inc(ll first, ll second, ll c) { return first <= second && second <= c; }
template <class t>
void mkuni(vc<t>& v) {
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
}
ll rand_int(ll l, ll r) {
  static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
  return uniform_int_distribution<ll>(l, r)(gen);
}
template <class t>
void myshuffle(vc<t>& first) {
  for (ll i = ll(0); i < ll(ll(first.size())); i++)
    swap(first[i], first[rand_int(0, i)]);
}
template <class t>
ll lwb(const vc<t>& v, const t& first) {
  return lower_bound(v.begin(), v.end(), first) - v.begin();
}
using uint = unsigned;
using ull = unsigned long long;
struct modinfo {
  uint mod, root;
};
template <modinfo const& ref>
struct modular {
  static constexpr uint const& mod = ref.mod;
  static modular root() { return modular(ref.root); }
  uint v;
  modular(ll vv = 0) { s(vv % mod + mod); }
  modular& s(uint vv) {
    v = vv < mod ? vv : vv - mod;
    return *this;
  }
  modular operator-() const { return modular() - *this; }
  modular& operator+=(const modular& rhs) { return s(v + rhs.v); }
  modular& operator-=(const modular& rhs) { return s(v + mod - rhs.v); }
  modular& operator*=(const modular& rhs) {
    v = ull(v) * rhs.v % mod;
    return *this;
  }
  modular& operator/=(const modular& rhs) { return *this *= rhs.inv(); }
  modular operator+(const modular& rhs) const { return modular(*this) += rhs; }
  modular operator-(const modular& rhs) const { return modular(*this) -= rhs; }
  modular operator*(const modular& rhs) const { return modular(*this) *= rhs; }
  modular operator/(const modular& rhs) const { return modular(*this) /= rhs; }
  modular pow(ll n) const {
    modular res(1), x(*this);
    while (n) {
      if (n & 1) res *= x;
      x *= x;
      n >>= 1;
    }
    return res;
  }
  modular inv() const { return pow(mod - 2); }
  friend modular operator+(ll x, const modular& y) { return modular(x) + y; }
  friend modular operator-(ll x, const modular& y) { return modular(x) - y; }
  friend modular operator*(ll x, const modular& y) { return modular(x) * y; }
  friend modular operator/(ll x, const modular& y) { return modular(x) / y; }
  friend ostream& operator<<(ostream& os, const modular& m) {
    return os << m.v;
  }
  friend istream& operator>>(istream& is, modular& m) {
    ll x;
    is >> x;
    m = modular(x);
    return is;
  }
  bool operator<(const modular& r) const { return v < r.v; }
  bool operator==(const modular& r) const { return v == r.v; }
  bool operator!=(const modular& r) const { return v != r.v; }
  explicit operator bool() const { return v; }
};
extern constexpr modinfo base{998244353, 3};
using mint = modular<base>;
const ll vmax = (1 << 21) + 10;
mint fact[vmax], finv[vmax], invs[vmax];
void initfact() {
  fact[0] = 1;
  for (ll i = ll(1); i < ll(vmax); i++) {
    fact[i] = fact[i - 1] * i;
  }
  finv[vmax - 1] = fact[vmax - 1].inv();
  for (ll i = vmax - 2; i >= 0; i--) {
    finv[i] = finv[i + 1] * (i + 1);
  }
  for (ll i = vmax - 1; i >= 1; i--) {
    invs[i] = finv[i] * fact[i - 1];
  }
}
mint choose(ll n, ll k) { return fact[n] * finv[n - k] * finv[k]; }
mint binom(ll first, ll second) {
  return fact[first + second] * finv[first] * finv[second];
}
mint catalan(ll n) {
  return binom(n, n) - (n - 1 >= 0 ? binom(n - 1, n + 1) : 0);
}
const ll V = ten(6);
ll readval() {
  double x;
  cin >> x;
  return min((ll)round(x * V), 30 * V);
}
const ll nmax = 35;
mint dp[2][nmax * nmax][nmax][nmax];
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  cout << fixed << setprecision(20);
  initfact();
  ll n;
  cin >> n;
  vi vs(n);
  for (ll i = ll(0); i < ll(n); i++) vs[i] = readval();
  for (ll i = ll(n - 1) - 1; i >= ll(0); i--) chmin(vs[i], vs[i + 1]);
  chmin(vs[0], V);
  vi hs{0};
  for (auto v : vs) {
    while (v > 0) {
      hs.push_back(v);
      v -= V;
    }
  }
  mkuni(hs);
  ll s = ll(hs.size()) - 1;
  vc<mint> dif(s);
  for (ll i = ll(0); i < ll(s); i++) dif[i] = mint(hs[i + 1] - hs[i]) / V;
  void(0);
  ll cur = 0;
  for (ll i = ll(0); i < ll(s); i++)
    if (hs[i] < vs[0]) {
      dp[cur][i][0][0] = dif[i];
    }
  for (ll i = ll(1); i < ll(n); i++) {
    ll nx = cur ^ 1;
    memset(dp[nx], 0, sizeof(dp[nx]));
    vc<mint> sum(n);
    for (ll j = ll(0); j < ll(s); j++)
      if (hs[j] < vs[i]) {
        for (ll k = ll(0); k < ll(n); k++)
          if (hs[j] < vs[i] - k * V) {
            dp[nx][j][k][0] = sum[k];
            if (k) dp[nx][j][k][0] -= sum[k - 1];
            for (ll ser = ll(1); ser < ll(i + 1); ser++) {
              dp[nx][j][k][ser] = dp[cur][j][k][ser - 1];
              if (k) dp[nx][j][k][ser] -= dp[cur][j][k - 1][ser - 1];
              dp[nx][j][k][ser] *= invs[ser + 1];
            }
            for (ll ser = ll(0); ser < ll(i + 1); ser++)
              dp[nx][j][k][ser] *= dif[j];
          }
        for (ll k = ll(0); k < ll(n); k++)
          if (hs[j] < vs[i - 1] - k * V) {
            for (ll ser = ll(0); ser < ll(i); ser++) {
              sum[k] += dp[cur][j][k][ser];
            }
          }
      }
    void(0);
    cur = nx;
  }
  mint ans = 0;
  for (ll i = ll(0); i < ll(s); i++)
    for (ll j = ll(0); j < ll(n); j++)
      for (ll k = ll(0); k < ll(n); k++) {
        ans += dp[cur][i][j][k];
        if (dp[cur][i][j][k]) {
          void(0);
        }
      }
  cout << ans << endl;
}

### Prompt

Your task is to create a Cpp solution to the following problem:

You generate real numbers s1, s2, ..., sn as follows: 

  * s0 = 0; 
  * si = si - 1 + ti, where ti is a real number chosen independently uniformly at random between 0 and 1, inclusive. 



You are given real numbers x1, x2, ..., xn. You are interested in the probability that si ≤ xi is true for all i simultaneously.

It can be shown that this can be represented as <image>, where P and Q are coprime integers, and <image>. Print the value of P·Q - 1 modulo 998244353.

Input

The first line contains integer n (1 ≤ n ≤ 30).

The next n lines contain real numbers x1, x2, ..., xn, given with at most six digits after the decimal point (0 < xi ≤ n).

Output

Print a single integer, the answer to the problem.

Examples

Input

4
1.00
2
3.000000
4.0


Output

1


Input

1
0.50216


Output

342677322


Input

2
0.5
1.0


Output

623902721


Input

6
0.77
1.234567
2.1
1.890
2.9999
3.77


Output

859831967

Note

In the first example, the sought probability is 1 since the sum of i real numbers which don't exceed 1 doesn't exceed i.

In the second example, the probability is x1 itself.

In the third example, the sought probability is 3 / 8.

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class t, class u>
void chmax(t& first, u second) {
  if (first < second) first = second;
}
template <class t, class u>
void chmin(t& first, u second) {
  if (second < first) first = second;
}
template <class t>
using vc = vector<t>;
template <class t>
using vvc = vc<vc<t>>;
using pi = pair<ll, ll>;
using vi = vc<ll>;
template <class t, class u>
ostream& operator<<(ostream& os, const pair<t, u>& p) {
  return os << "{" << p.first << "," << p.second << "}";
}
template <class t>
ostream& operator<<(ostream& os, const vc<t>& v) {
  os << "{";
  for (auto e : v) os << e << ",";
  return os << "}";
}
using uint = unsigned;
using ull = unsigned long long;
template <class t, size_t n>
ostream& operator<<(ostream& os, const array<t, n>& first) {
  return os << vc<t>(first.begin(), first.end());
}
template <ll i, class T>
void print_tuple(ostream&, const T&) {}
template <ll i, class T, class H, class... Args>
void print_tuple(ostream& os, const T& t) {
  if (i) os << ",";
  os << get<i>(t);
  print_tuple<i + 1, T, Args...>(os, t);
}
template <class... Args>
ostream& operator<<(ostream& os, const tuple<Args...>& t) {
  os << "{";
  print_tuple<0, tuple<Args...>, Args...>(os, t);
  return os << "}";
}
template <class t>
void print(t x, ll suc = 1) {
  cout << x;
  if (suc == 1) cout << "\n";
  if (suc == 2) cout << " ";
}
ll read() {
  ll i;
  cin >> i;
  return i;
}
vi readvi(ll n, ll off = 0) {
  vi v(n);
  for (ll i = ll(0); i < ll(n); i++) v[i] = read() + off;
  return v;
}
template <class T>
void print(const vector<T>& v, ll suc = 1) {
  for (ll i = ll(0); i < ll(v.size()); i++)
    print(v[i], i == ll(v.size()) - 1 ? suc : 2);
}
string readString() {
  string s;
  cin >> s;
  return s;
}
template <class T>
T sq(const T& t) {
  return t * t;
}
void yes(bool ex = true) {
  cout << "Yes"
       << "\n";
  if (ex) exit(0);
}
void no(bool ex = true) {
  cout << "No"
       << "\n";
  if (ex) exit(0);
}
void possible(bool ex = true) {
  cout << "Possible"
       << "\n";
  if (ex) exit(0);
}
void impossible(bool ex = true) {
  cout << "Impossible"
       << "\n";
  if (ex) exit(0);
}
constexpr ll ten(ll n) { return n == 0 ? 1 : ten(n - 1) * 10; }
const ll infLL = LLONG_MAX / 3;
const ll inf = infLL;
ll topbit(signed t) { return t == 0 ? -1 : 31 - __builtin_clz(t); }
ll topbit(ll t) { return t == 0 ? -1 : 63 - __builtin_clzll(t); }
ll botbit(signed first) { return first == 0 ? 32 : __builtin_ctz(first); }
ll botbit(ll first) { return first == 0 ? 64 : __builtin_ctzll(first); }
ll popcount(signed t) { return __builtin_popcount(t); }
ll popcount(ll t) { return __builtin_popcountll(t); }
bool ispow2(ll i) { return i && (i & -i) == i; }
ll mask(ll i) { return (ll(1) << i) - 1; }
bool inc(ll first, ll second, ll c) { return first <= second && second <= c; }
template <class t>
void mkuni(vc<t>& v) {
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
}
ll rand_int(ll l, ll r) {
  static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
  return uniform_int_distribution<ll>(l, r)(gen);
}
template <class t>
void myshuffle(vc<t>& first) {
  for (ll i = ll(0); i < ll(ll(first.size())); i++)
    swap(first[i], first[rand_int(0, i)]);
}
template <class t>
ll lwb(const vc<t>& v, const t& first) {
  return lower_bound(v.begin(), v.end(), first) - v.begin();
}
using uint = unsigned;
using ull = unsigned long long;
struct modinfo {
  uint mod, root;
};
template <modinfo const& ref>
struct modular {
  static constexpr uint const& mod = ref.mod;
  static modular root() { return modular(ref.root); }
  uint v;
  modular(ll vv = 0) { s(vv % mod + mod); }
  modular& s(uint vv) {
    v = vv < mod ? vv : vv - mod;
    return *this;
  }
  modular operator-() const { return modular() - *this; }
  modular& operator+=(const modular& rhs) { return s(v + rhs.v); }
  modular& operator-=(const modular& rhs) { return s(v + mod - rhs.v); }
  modular& operator*=(const modular& rhs) {
    v = ull(v) * rhs.v % mod;
    return *this;
  }
  modular& operator/=(const modular& rhs) { return *this *= rhs.inv(); }
  modular operator+(const modular& rhs) const { return modular(*this) += rhs; }
  modular operator-(const modular& rhs) const { return modular(*this) -= rhs; }
  modular operator*(const modular& rhs) const { return modular(*this) *= rhs; }
  modular operator/(const modular& rhs) const { return modular(*this) /= rhs; }
  modular pow(ll n) const {
    modular res(1), x(*this);
    while (n) {
      if (n & 1) res *= x;
      x *= x;
      n >>= 1;
    }
    return res;
  }
  modular inv() const { return pow(mod - 2); }
  friend modular operator+(ll x, const modular& y) { return modular(x) + y; }
  friend modular operator-(ll x, const modular& y) { return modular(x) - y; }
  friend modular operator*(ll x, const modular& y) { return modular(x) * y; }
  friend modular operator/(ll x, const modular& y) { return modular(x) / y; }
  friend ostream& operator<<(ostream& os, const modular& m) {
    return os << m.v;
  }
  friend istream& operator>>(istream& is, modular& m) {
    ll x;
    is >> x;
    m = modular(x);
    return is;
  }
  bool operator<(const modular& r) const { return v < r.v; }
  bool operator==(const modular& r) const { return v == r.v; }
  bool operator!=(const modular& r) const { return v != r.v; }
  explicit operator bool() const { return v; }
};
extern constexpr modinfo base{998244353, 3};
using mint = modular<base>;
const ll vmax = (1 << 21) + 10;
mint fact[vmax], finv[vmax], invs[vmax];
void initfact() {
  fact[0] = 1;
  for (ll i = ll(1); i < ll(vmax); i++) {
    fact[i] = fact[i - 1] * i;
  }
  finv[vmax - 1] = fact[vmax - 1].inv();
  for (ll i = vmax - 2; i >= 0; i--) {
    finv[i] = finv[i + 1] * (i + 1);
  }
  for (ll i = vmax - 1; i >= 1; i--) {
    invs[i] = finv[i] * fact[i - 1];
  }
}
mint choose(ll n, ll k) { return fact[n] * finv[n - k] * finv[k]; }
mint binom(ll first, ll second) {
  return fact[first + second] * finv[first] * finv[second];
}
mint catalan(ll n) {
  return binom(n, n) - (n - 1 >= 0 ? binom(n - 1, n + 1) : 0);
}
const ll V = ten(6);
ll readval() {
  double x;
  cin >> x;
  return min((ll)round(x * V), 30 * V);
}
const ll nmax = 35;
mint dp[2][nmax * nmax][nmax][nmax];
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  cout << fixed << setprecision(20);
  initfact();
  ll n;
  cin >> n;
  vi vs(n);
  for (ll i = ll(0); i < ll(n); i++) vs[i] = readval();
  for (ll i = ll(n - 1) - 1; i >= ll(0); i--) chmin(vs[i], vs[i + 1]);
  chmin(vs[0], V);
  vi hs{0};
  for (auto v : vs) {
    while (v > 0) {
      hs.push_back(v);
      v -= V;
    }
  }
  mkuni(hs);
  ll s = ll(hs.size()) - 1;
  vc<mint> dif(s);
  for (ll i = ll(0); i < ll(s); i++) dif[i] = mint(hs[i + 1] - hs[i]) / V;
  void(0);
  ll cur = 0;
  for (ll i = ll(0); i < ll(s); i++)
    if (hs[i] < vs[0]) {
      dp[cur][i][0][0] = dif[i];
    }
  for (ll i = ll(1); i < ll(n); i++) {
    ll nx = cur ^ 1;
    memset(dp[nx], 0, sizeof(dp[nx]));
    vc<mint> sum(n);
    for (ll j = ll(0); j < ll(s); j++)
      if (hs[j] < vs[i]) {
        for (ll k = ll(0); k < ll(n); k++)
          if (hs[j] < vs[i] - k * V) {
            dp[nx][j][k][0] = sum[k];
            if (k) dp[nx][j][k][0] -= sum[k - 1];
            for (ll ser = ll(1); ser < ll(i + 1); ser++) {
              dp[nx][j][k][ser] = dp[cur][j][k][ser - 1];
              if (k) dp[nx][j][k][ser] -= dp[cur][j][k - 1][ser - 1];
              dp[nx][j][k][ser] *= invs[ser + 1];
            }
            for (ll ser = ll(0); ser < ll(i + 1); ser++)
              dp[nx][j][k][ser] *= dif[j];
          }
        for (ll k = ll(0); k < ll(n); k++)
          if (hs[j] < vs[i - 1] - k * V) {
            for (ll ser = ll(0); ser < ll(i); ser++) {
              sum[k] += dp[cur][j][k][ser];
            }
          }
      }
    void(0);
    cur = nx;
  }
  mint ans = 0;
  for (ll i = ll(0); i < ll(s); i++)
    for (ll j = ll(0); j < ll(n); j++)
      for (ll k = ll(0); k < ll(n); k++) {
        ans += dp[cur][i][j][k];
        if (dp[cur][i][j][k]) {
          void(0);
        }
      }
  cout << ans << endl;
}

```