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CF438E The Child and Binary Tree

设权值为的答案为,对应OGF为,集合对应的OGF为

考虑,枚举二叉树左右子树的方案数和根的值,可得

均大于0,所以只有为空树的一种情况即,可得

,代入 ,可得

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#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/trie_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/priority_queue.hpp>

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
typedef long long ll;
//tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> tr;
//__gnu_pbds::priority_queue<int, greater<int>, pairing_heap_tag> qu;
//typedef trie<string, null_type, trie_string_access_traits<>, pat_trie_tag, trie_prefix_search_node_update> pref_trie;
const int N = 200005;
int n, m, k;
namespace polybase {//范围为1e9需要先取模,别忘记改模数
const ll mod = 998244353;
int limit;
ll _wn[25];

ll fpow(ll x, ll r)
{
ll result = 1;
while (r)
{
if (r & 1)result = result * x % mod;
r >>= 1;
x = x * x % mod;
}
return result;
}

int _ = []
{
for (int i = 0; i <= 23; i++)_wn[i] = fpow(3, (mod - 1) >> i);
return 0;
}();

inline int norm(int n) { return 1 << __lg(n * 2 - 1); }

void NTT(ll *A, int type)
{
int i, j = limit >> 1, k, l, c = 0;
ll u, v, w, wn;
for (i = 1; i < limit - 1; i++)
{
if (i < j)swap(A[i], A[j]);
for (k = limit >> 1; (j ^= k) < k; k >>= 1);
}

for (l = 2; l <= limit; l <<= 1)
{
i = l >> 1, wn = _wn[++c];
for (j = 0; j < limit; j += l)
{
w = 1;
for (k = j; k < j + i; k++)
{
u = A[k], v = A[k + i] * w % mod;
A[k] = u + v;
if (A[k] >= mod)A[k] -= mod;

A[k + i] = u - v;
if (A[k + i] < 0)A[k + i] += mod;
w = w * wn % mod;
}
}
}
if (type == -1)
{
ll inv = fpow(limit, mod - 2);
for (i = 0; i < limit; i++)A[i] = A[i] * inv % mod;
for (i = 1; i < limit / 2; i++)swap(A[i], A[limit - i]);
}
}

struct poly : public vector<ll>
{
using vector<ll>::vector;
#define T (*this)

poly modxk(int k) const
{
k = min(k, (int) size());
return poly(begin(), begin() + k);
}

poly rev() const { return poly(rbegin(), rend()); }

friend void NTT(poly &a, const int type) { NTT(a.data(), type); }

friend poly operator*(const poly &x, const poly &y)
{
if (x.empty() || y.empty())return poly();
poly a(x), b(y);
int len = a.size() + b.size() - 1;
limit = norm(len);
a.resize(limit), b.resize(limit);
NTT(a, 1);
NTT(b, 1);
for (int i = 0; i < limit; i++)
a[i] = a[i] * b[i] % mod;
NTT(a, -1);
a.resize(len);
return a;
}

poly operator+(const poly &b)
{
poly a(T);
if (a.size() < b.size())
a.resize(b.size());
for (int i = 0; i < b.size(); i++)//用b.size()防止越界
{
a[i] += b[i];
if (a[i] >= mod)a[i] -= mod;
}
return a;
}

poly operator-(const poly &b)
{
poly a(T);
if (a.size() < b.size())
a.resize(b.size());
for (int i = 0; i < b.size(); i++)
{
a[i] -= b[i];
if (a[i] < 0)a[i] += mod;
}
return a;
}

poly operator*(const ll p)
{
poly a(T);
for (auto &x:a)
x = x * p % mod;
return a;
}

poly &operator<<=(int r) { return insert(begin(), r, 0), T; }//注意逗号,F(x)*(x^r)

poly operator<<(int r) const { return poly(T) <<= r; }

poly operator>>(int r) const { return r >= size() ? poly() : poly(begin() + r, end()); }

poly &operator>>=(int r) { return T = T >> r; }//F[x]/(x^r)

poly deriv()//求导
{
if (empty())return T;
poly a(size() - 1);
for (int i = 1; i < size(); i++)//注意是size()
a[i - 1] = T[i] * i % mod;
return a;
}

poly integ()//积分
{
poly a(size() + 1);
for (int i = 1; i < a.size(); i++)//注意是a.size()
a[i] = T[i - 1] * fpow(i, mod - 2) % mod;
return a;
}

poly inv(int n)
{
poly a{fpow(T[0], mod - 2)};
int k = 1;
while (k < n)
{
k <<= 1;
a = (a * 2 - modxk(k) * a * a).modxk(k);
}
return a.modxk(n);
}

poly sqrt(int n)//f[0]必须等于1
{
poly a{1};
int k = 1;
const ll inv2 = fpow(2, mod - 2);
while (k < n)
{
k <<= 1;
a = ((modxk(k) * a.inv(k)).modxk(k) + a) * inv2;
}
return a.modxk(n);
}

poly ln(int n)//需要保证f[0]=1
{
return (deriv() * inv(n)).integ().modxk(n);
}

#undef T
};
}
using namespace polybase;

int main()
{
int p, q, u, v, w, x, y, z, T;
cin >> n >> m;
poly C(m + 1);
for (int i = 1; i <= n; i++)
{
scanf("%d", &x);
if (x <= m)
C[x] = 1;
}
poly F = (poly{1} + (poly{1} - C * 4).sqrt(m + 1)).inv(m + 1) * 2;
for (int i = 1; i <= m; i++)
printf("%d\n", F[i]);
return 0;
}