QOJ.ac
QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#576273 | #8339. Rooted Tree | guodong | AC ✓ | 1130ms | 8004kb | C++14 | 12.7kb | 2024-09-19 19:45:01 | 2024-09-19 19:45:02 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#define debug(...) fprintf(stderr, ##__VA_ARGS__)
#else
#define debug(...) void(0)
#endif
typedef long long LL;
template <unsigned umod>
struct modint {
static constexpr int mod = umod;
unsigned v;
modint() : v(0) {}
template <class T, enable_if_t<is_integral<T>::value>* = nullptr>
modint(T x) {
x %= mod;
if (x < 0) x += mod;
v = x;
}
modint(const string& str) {
v = 0;
size_t i = 0;
if (str.front() == '-') i += 1;
while (i < str.size()) {
assert(isdigit(str[i]));
v = (v * 10ull % umod + str[i] - '0') % umod;
i += 1;
}
if (str.front() == '-' && v) v = umod - v;
}
modint operator+() const { return *this; }
modint operator-() const { return modint() - *this; }
friend int raw(const modint& self) { return self.v; }
friend istream& operator>>(istream& is, modint& self) {
string str;
is >> str;
self = str;
return is;
}
friend ostream& operator<<(ostream& os, const modint& self) {
return os << raw(self);
}
modint& operator+=(const modint& rhs) {
v += rhs.v;
if (v >= umod) v -= umod;
return *this;
}
modint& operator-=(const modint& rhs) {
v -= rhs.v;
if (v >= umod) v += umod;
return *this;
}
modint& operator*=(const modint& rhs) {
v = static_cast<unsigned>(1ull * v * rhs.v % umod);
return *this;
}
modint& operator/=(const modint& rhs) {
static constexpr size_t ilim = 1 << 20;
static modint inv[ilim + 10];
static int sz = 0;
assert(rhs.v);
if (rhs.v > ilim) return *this *= qpow(rhs, mod - 2);
if (!sz) inv[1] = sz = 1;
while (sz < (int)rhs.v) {
for (int i = sz + 1; i <= sz << 1; i++) inv[i] = -mod / i * inv[mod % i];
sz <<= 1;
}
return *this *= inv[rhs.v];
}
template <class T>
friend modint qpow(modint a, T b) {
modint r = 1;
for (; b; b >>= 1, a *= a)
if (b & 1) r *= a;
return r;
}
friend modint operator+(modint lhs, const modint& rhs) { return lhs += rhs; }
friend modint operator-(modint lhs, const modint& rhs) { return lhs -= rhs; }
friend modint operator*(modint lhs, const modint& rhs) { return lhs *= rhs; }
friend modint operator/(modint lhs, const modint& rhs) { return lhs /= rhs; }
friend bool operator==(const modint& lhs, const modint& rhs) {
return lhs.v == rhs.v;
}
friend bool operator!=(const modint& lhs, const modint& rhs) {
return lhs.v != rhs.v;
}
};
const int Mod = 1e9 + 9;
typedef modint<Mod> mint;
int glim(const int& x) { return 1 << (32 - __builtin_clz(x - 1)); }
int bitctz(const int& x) { return __builtin_ctz(x); }
struct poly : vector<mint> {
poly() {}
explicit poly(int n) : vector<mint>(n) {}
poly(const vector<mint>& vec) : vector<mint>(vec) {}
poly(initializer_list<mint> il) : vector<mint>(il) {}
mint operator()(const mint& x) const;
poly& cut(int lim);
void ntt(int op);
};
void print(const poly& a) {
for (size_t i = 0; i < a.size(); i++) debug("%d, ", raw(a[i]));
debug("\n");
}
istream& operator>>(istream& is, poly& a) {
for (auto& x : a) is >> x;
return is;
}
ostream& operator<<(ostream& os, const poly& a) {
bool flag = false;
for (auto& x : a) {
if (flag)
os << " ";
else
flag = true;
os << x;
}
return os;
}
mint poly::operator()(const mint& x) const {
const auto& a = *this;
mint res = 0;
for (int i = (int)a.size() - 1; i >= 0; i--) {
res = res * x + a[i];
}
return res;
}
poly& poly::cut(int lim) {
resize(lim);
return *this;
}
void poly::ntt(int op) {
static bool wns_flag = false;
static vector<mint> wns;
if (!wns_flag) {
wns_flag = true;
for (int j = 1; j <= 23; j++) {
wns.push_back(qpow(mint(3), raw(mint(-1)) >> j));
}
}
vector<mint>& a = *this;
int n = a.size();
for (int i = 1, r = 0; i < n; i++) {
r ^= n - (1 << (bitctz(n) - bitctz(i) - 1));
if (i < r) std::swap(a[i], a[r]);
}
vector<mint> w(n);
for (int k = 1, len = 2; len <= n; k <<= 1, len <<= 1) {
mint wn = wns[bitctz(k)];
for (int i = raw(w[0] = 1); i < k; i++) w[i] = w[i - 1] * wn;
for (int i = 0; i < n; i += len) {
for (int j = 0; j < k; j++) {
mint x = a[i + j], y = a[i + j + k] * w[j];
a[i + j] = x + y, a[i + j + k] = x - y;
}
}
}
if (op == -1) {
mint iz = mint(1) / n;
for (int i = 0; i < n; i++) a[i] *= iz;
reverse(a.begin() + 1, a.end());
}
}
poly concalc(int n, vector<poly> vec,
const function<mint(vector<mint>)>& func) {
int lim = glim(n);
int m = vec.size();
for (auto& f : vec) f.resize(lim), f.ntt(1);
vector<mint> tmp(m);
poly ret(lim);
for (int i = 0; i < lim; i++) {
for (int j = 0; j < m; j++) tmp[j] = vec[j][i];
ret[i] = func(tmp);
}
ret.ntt(-1);
return ret;
}
poly getInv(const poly& a, int lim) {
poly b{1 / a[0]};
for (int len = 2; len <= glim(lim); len <<= 1) {
poly c = vector<mint>(a.begin(), a.begin() + min(len, (int)a.size()));
b = concalc(len << 1, {b, c}, [](vector<mint> vec) {
return vec[0] * (2 - vec[0] * vec[1]);
}).cut(len);
}
return b.cut(lim);
}
poly operator+=(poly& a, const poly& b) {
if (a.size() < b.size()) a.resize(b.size());
for (size_t i = 0; i < b.size(); i++) a[i] += b[i];
return a;
}
poly operator-=(poly& a, const poly& b) {
if (a.size() < b.size()) a.resize(b.size());
for (size_t i = 0; i < b.size(); i++) a[i] -= b[i];
return a;
}
poly operator*=(poly& a, const mint& k) {
if (k == 1) return a;
for (size_t i = 0; i < a.size(); i++) a[i] *= k;
return a;
}
poly operator/=(poly& a, const mint& k) { return a *= 1 / k; }
poly operator<<=(poly& a, const int& k) {
// mnltiple by x^k
a.insert(a.begin(), k, 0);
return a;
}
poly operator>>=(poly& a, const int& k) {
// divide by x^k
a.erase(a.begin(), a.begin() + min(k, (int)a.size()));
return a;
}
poly operator*(const poly& a, const poly& b) {
if (a.empty() || b.empty()) return {};
int rlen = a.size() + b.size() - 1;
int len = glim(rlen);
if (1ull * a.size() * b.size() <= 1ull * len * bitctz(len)) {
poly ret(rlen);
for (size_t i = 0; i < a.size(); i++)
for (size_t j = 0; j < b.size(); j++) ret[i + j] += a[i] * b[j];
return ret;
} else {
return concalc(len, {a, b},
[](vector<mint> vec) { return vec[0] * vec[1]; })
.cut(rlen);
}
}
poly operator/(poly a, poly b) {
if (a.size() < b.size()) return {};
int rlen = a.size() - b.size() + 1;
reverse(a.begin(), a.end());
reverse(b.begin(), b.end());
a = (a * getInv(b, rlen)).cut(rlen);
reverse(a.begin(), a.end());
return a;
}
poly operator-(poly a, const poly& b) { return a -= b; }
poly operator%(const poly& a, const poly& b) {
return (a - (a / b) * b).cut(b.size() - 1);
}
poly operator*=(poly& a, const poly& b) { return a = a * b; }
poly operator/=(poly& a, const poly& b) { return a = a / b; }
poly operator%=(poly& a, const poly& b) { return a = a % b; }
poly operator+(poly a, const poly& b) { return a += b; }
poly operator*(poly a, const mint& k) { return a *= k; }
poly operator*(const mint& k, poly a) { return a *= k; }
poly operator/(poly a, const mint& k) { return a /= k; }
poly operator<<(poly a, const int& k) { return a <<= k; }
poly operator>>(poly a, const int& k) { return a >>= k; }
poly getDev(poly a) {
a >>= 1;
for (size_t i = 1; i < a.size(); i++) a[i] *= i + 1;
return a;
}
poly getInt(poly a) {
a <<= 1;
for (size_t i = 1; i < a.size(); i++) a[i] /= i;
return a;
}
poly getLn(const poly& a, int lim) {
assert(a[0] == 1);
return getInt(getDev(a) * getInv(a, lim)).cut(lim);
}
poly getExp(const poly& a, int lim) {
assert(a[0] == 0);
poly b{1};
for (int len = 2; len <= glim(lim); len <<= 1) {
poly c = vector<mint>(a.begin(), a.begin() + min(len, (int)a.size()));
b = concalc(len << 1, {b, getLn(b, len), c}, [](vector<mint> vec) {
return vec[0] * (1 - vec[1] + vec[2]);
}).cut(len);
}
return b.cut(lim);
}
poly qpow(const poly& a, string k, int lim) {
size_t i = 0;
while (i < a.size() && a[i] == 0) i += 1;
if (i == a.size() || (i > 0 && k.size() >= 9) ||
1ull * i * raw(mint(k)) >= 1ull * lim)
return poly(lim);
lim -= i * raw(mint(k));
return getExp(getLn(a / a[i] >> i, lim) * k, lim) *
qpow(a[i], raw(modint<mint::mod - 1>(k)))
<< i * raw(mint(k));
}
poly qpow(const poly& a, LL k, int lim) {
size_t i = 0;
while (i < a.size() && a[i] == 0) i += 1;
if (i == a.size() || (i > 0 && k >= 1e9) ||
1ull * i * k >= 1ull * lim)
return poly(lim);
lim -= i * k;
return getExp(getLn(a / a[i] >> i, lim) * k, lim) *
qpow(a[i], raw(modint<mint::mod - 1>(k)))
<< i * k;
}
mint sqrt(const mint& c) {
static const auto check = [](mint c) {
return qpow(c, (mint::mod - 1) >> 1) == 1;
};
if (raw(c) <= 1) return 1;
if (!check(c)) throw "No solution!";
static mt19937 rng{random_device{}()};
mint a = rng();
while (check(a * a - c)) a = rng();
typedef pair<mint, mint> number;
const auto mul = [=](number x, number y) {
return make_pair(x.first * y.first + x.second * y.second * (a * a - c),
x.first * y.second + x.second * y.first);
};
const auto qpow = [=](number a, int b) {
number r = {1, 0};
for (; b; b >>= 1, a = mul(a, a))
if (b & 1) r = mul(r, a);
return r;
};
mint ret = qpow({a, 1}, (mint::mod + 1) >> 1).first;
return min(raw(ret), raw(-ret));
}
poly getSqrt(const poly& a, int lim) {
poly b{sqrt(a[0])};
for (int len = 2; len <= glim(lim); len <<= 1) {
poly c = vector<mint>(a.begin(), a.begin() + min(len, (int)a.size()));
b = (c * getInv(b * 2, len) + b / 2).cut(len);
}
return b.cut(lim);
}
template <class T>
mint divide_at(poly f, poly g, T n) {
for (; n; n >>= 1) {
poly r = g;
for (size_t i = 1; i < r.size(); i += 2) r[i] *= -1;
f *= r;
g *= r;
for (size_t i = n & 1; i < f.size(); i += 2) f[i >> 1] = f[i];
f.resize((f.size() + 1) >> 1);
for (size_t i = 0; i < g.size(); i += 2) g[i >> 1] = g[i];
g.resize((g.size() + 1) >> 1);
}
return f.empty() ? 0 : f[0] / g[0];
}
template <class T>
mint linear_rec(poly a, poly f, T n) {
// a[n] = sum_i f[i] * a[n - i]
a.resize(f.size() - 1);
f = poly{1} - f;
poly g = a * f;
g.resize(a.size());
return divide_at(g, f, n);
}
poly BM(poly a) {
poly ans, lst;
int w = 0;
mint delta = 0;
for (size_t i = 0; i < a.size(); i++) {
mint tmp = -a[i];
for (size_t j = 0; j < ans.size(); j++) tmp += ans[j] * a[i - j - 1];
if (tmp == 0) continue;
if (ans.empty()) {
w = i;
delta = tmp;
ans = vector<mint>(i + 1, 0);
} else {
auto now = ans;
mint mul = -tmp / delta;
if (ans.size() < lst.size() + i - w) ans.resize(lst.size() + i - w);
ans[i - w - 1] -= mul;
for (size_t j = 0; j < lst.size(); j++) ans[i - w + j] += lst[j] * mul;
if (now.size() <= lst.size() + i - w) {
w = i;
lst = now;
delta = tmp;
}
}
}
return ans << 1;
}
poly lagrange(const vector<pair<mint, mint>>& a) {
poly ans(a.size()), product{1};
for (size_t i = 0; i < a.size(); i++) {
product *= poly{-a[i].first, 1};
}
auto divide2 = [&](poly a, mint b) {
poly res(a.size() - 1);
for (size_t i = (int)a.size() - 1; i >= 1; i--) {
res[i - 1] = a[i];
a[i - 1] -= a[i] * b;
}
return res;
};
for (size_t i = 0; i < a.size(); i++) {
mint denos = 1;
for (size_t j = 0; j < a.size(); j++) {
if (i != j) denos *= a[i].first - a[j].first;
}
poly numes = divide2(product, -a[i].first);
ans += a[i].second / denos * numes;
}
return ans;
}
#define For(i,a,b) for(int i =a ; i <=b ;++i)
#define mp make_pair
#define int long long
mint A[2],L[2],D[2];
signed main() {
#ifdef NICEGUODONG
freopen("data.in","r",stdin);
// freopen("b.out","w",stdout);
auto start = std::chrono::high_resolution_clock::now();
#endif
ios::sync_with_stdio(false);
D[0] = 1;
A[0] = 0;
L[0] = 0;
mint m;
cin >> m;
int k;
cin >> k;
For(i,1,k){
int now = i & 1;
int pre = 1 - now;
A[now] = (L[pre] + 1) * m + A[pre];
D[now] = D[pre] + m - 1;
L[now] = (D[pre] * L[pre] - L[pre] + (L[pre] + 1) * m) / D[now];
}
cout << A[k & 1] << '\n';
#ifdef NICEGUODONG
auto end = std::chrono::high_resolution_clock::now();
std::chrono::duration<double> duration = end - start;
std::cerr << "Runtime: " << duration.count() << " sec" << std::endl;
return 0;
#endif
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 1ms
memory: 7780kb
input:
6 2
output:
18
result:
ok 1 number(s): "18"
Test #2:
score: 0
Accepted
time: 2ms
memory: 7720kb
input:
2 6
output:
600000038
result:
ok 1 number(s): "600000038"
Test #3:
score: 0
Accepted
time: 70ms
memory: 7716kb
input:
83 613210
output:
424200026
result:
ok 1 number(s): "424200026"
Test #4:
score: 0
Accepted
time: 756ms
memory: 7764kb
input:
48 6713156
output:
198541581
result:
ok 1 number(s): "198541581"
Test #5:
score: 0
Accepted
time: 1ms
memory: 7708kb
input:
1 111
output:
6216
result:
ok 1 number(s): "6216"
Test #6:
score: 0
Accepted
time: 823ms
memory: 7808kb
input:
28 7304152
output:
457266679
result:
ok 1 number(s): "457266679"
Test #7:
score: 0
Accepted
time: 465ms
memory: 7776kb
input:
38 4101162
output:
232117382
result:
ok 1 number(s): "232117382"
Test #8:
score: 0
Accepted
time: 1119ms
memory: 7968kb
input:
51 9921154
output:
340670552
result:
ok 1 number(s): "340670552"
Test #9:
score: 0
Accepted
time: 208ms
memory: 7776kb
input:
79 1801157
output:
620550406
result:
ok 1 number(s): "620550406"
Test #10:
score: 0
Accepted
time: 610ms
memory: 7712kb
input:
22 5417157
output:
457449071
result:
ok 1 number(s): "457449071"
Test #11:
score: 0
Accepted
time: 359ms
memory: 8004kb
input:
25 3210162
output:
36368303
result:
ok 1 number(s): "36368303"
Test #12:
score: 0
Accepted
time: 333ms
memory: 7664kb
input:
67 2919160
output:
935195555
result:
ok 1 number(s): "935195555"
Test #13:
score: 0
Accepted
time: 973ms
memory: 7712kb
input:
77 8613163
output:
482832472
result:
ok 1 number(s): "482832472"
Test #14:
score: 0
Accepted
time: 1126ms
memory: 7704kb
input:
90 10000000
output:
275581651
result:
ok 1 number(s): "275581651"
Test #15:
score: 0
Accepted
time: 1130ms
memory: 7644kb
input:
99 9999999
output:
126087169
result:
ok 1 number(s): "126087169"
Test #16:
score: 0
Accepted
time: 1130ms
memory: 7740kb
input:
100 10000000
output:
451590067
result:
ok 1 number(s): "451590067"
Extra Test:
score: 0
Extra Test Passed