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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#130851 | #618. 多项式乘法 | GoatGirl98# | Compile Error | / | / | C11 | 43.5kb | 2023-07-25 14:10:13 | 2023-07-25 14:10:17 |
Judging History
你现在查看的是最新测评结果
- [2023-08-10 23:21:45]
- System Update: QOJ starts to keep a history of the judgings of all the submissions.
- [2023-07-25 14:10:17]
- 评测
- 测评结果:Compile Error
- 用时:0ms
- 内存:0kb
- [2023-07-25 14:10:13]
- 提交
answer
// Polynomial test From HOS
#include <assert.h>
#include <string.h>
#include <algorithm>
#include <initializer_list>
#include <vector>
#ifndef LIBRA_ALGEBRA_FFT_998244353_H_
#define LIBRA_ALGEBRA_FFT_998244353_H_
#include <assert.h>
#include <vector>
#ifndef LIBRA_ALGEBRA_MODINT_H_
#define LIBRA_ALGEBRA_MODINT_H_
#include <stdio.h>
typedef long long ll;
namespace FastIO
{
char buf[1 << 21], *p1 = buf, *p2 = buf;
inline char nc() { return p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 21, stdin), p1 == p2) ? EOF : *p1++; }
ll rd()
{
ll ret = 0, f = 1;
char ch = nc();
while (ch < '0' || ch > '9')
{
if (ch == '-')
f = -1;
ch = nc();
}
while (ch >= '0' && ch <= '9')
{
ret = (ret << 1) + (ret << 3) + (ch ^ 48);
ch = nc();
}
return f == 1 ? ret : -ret;
}
char Buf[1 << 21], out[20];
int P, out_size;
void flush() { fwrite(Buf, 1, out_size, stdout), out_size = 0; }
void wt(ll x, char ch)
{
if (out_size >= 1 << 20)
flush();
if (x < 0)
Buf[out_size++] = 45, x = -x;
do
out[++P] = (x % 10) ^ 48;
while (x /= 10);
do
Buf[out_size++] = out[P];
while (--P);
Buf[out_size++] = ch;
}
struct IOFlush
{
~IOFlush() { flush(); }
} tail;
}
////////////////////////////////////////////////////////////////////////////////
template <unsigned M_>
struct ModInt
{
static constexpr unsigned M = M_;
unsigned x;
constexpr ModInt() : x(0U) {}
constexpr ModInt(unsigned x_) : x(x_ % M) {}
constexpr ModInt(unsigned long long x_) : x(x_ % M) {}
constexpr ModInt(int x_) : x(((x_ %= static_cast<int>(M)) < 0) ? (x_ + static_cast<int>(M)) : x_) {}
constexpr ModInt(long long x_) : x(((x_ %= static_cast<long long>(M)) < 0) ? (x_ + static_cast<long long>(M)) : x_) {}
ModInt &operator+=(const ModInt &a)
{
x = ((x += a.x) >= M) ? (x - M) : x;
return *this;
}
ModInt &operator-=(const ModInt &a)
{
x = ((x -= a.x) >= M) ? (x + M) : x;
return *this;
}
ModInt &operator*=(const ModInt &a)
{
x = (static_cast<unsigned long long>(x) * a.x) % M;
return *this;
}
ModInt &operator/=(const ModInt &a) { return (*this *= a.inv()); }
ModInt pow(long long e) const
{
if (e < 0)
return inv().pow(-e);
ModInt a = *this, b = 1U;
for (; e; e >>= 1)
{
if (e & 1)
b *= a;
a *= a;
}
return b;
}
ModInt inv() const
{
unsigned a = M, b = x;
int y = 0, z = 1;
for (; b;)
{
const unsigned q = a / b;
const unsigned c = a - q * b;
a = b;
b = c;
const int w = y - static_cast<int>(q) * z;
y = z;
z = w;
}
assert(a == 1U);
return ModInt(y);
}
ModInt operator+() const { return *this; }
ModInt operator-() const
{
ModInt a;
a.x = x ? (M - x) : 0U;
return a;
}
ModInt operator+(const ModInt &a) const { return (ModInt(*this) += a); }
ModInt operator-(const ModInt &a) const { return (ModInt(*this) -= a); }
ModInt operator*(const ModInt &a) const { return (ModInt(*this) *= a); }
ModInt operator/(const ModInt &a) const { return (ModInt(*this) /= a); }
template <class T>
friend ModInt operator+(T a, const ModInt &b) { return (ModInt(a) += b); }
template <class T>
friend ModInt operator-(T a, const ModInt &b) { return (ModInt(a) -= b); }
template <class T>
friend ModInt operator*(T a, const ModInt &b) { return (ModInt(a) *= b); }
template <class T>
friend ModInt operator/(T a, const ModInt &b) { return (ModInt(a) /= b); }
explicit operator bool() const { return x; }
bool operator==(const ModInt &a) const { return (x == a.x); }
bool operator!=(const ModInt &a) const { return (x != a.x); }
// friend std::ostream &operator<<(std::ostream &os, const ModInt &a) { return os << a.x; }
};
////////////////////////////////////////////////////////////////////////////////
#endif // LIBRA_ALGEBRA_MODINT_H_
using std::vector;
////////////////////////////////////////////////////////////////////////////////
constexpr unsigned MO = 998244353U;
constexpr unsigned MO2 = 2U * MO;
constexpr int FFT_MAX = 23;
using Mint = ModInt<MO>;
constexpr Mint FFT_ROOTS[FFT_MAX + 1] = {1U, 998244352U, 911660635U, 372528824U, 929031873U, 452798380U, 922799308U, 781712469U, 476477967U, 166035806U, 258648936U, 584193783U, 63912897U, 350007156U, 666702199U, 968855178U, 629671588U, 24514907U, 996173970U, 363395222U, 565042129U, 733596141U, 267099868U, 15311432U};
constexpr Mint INV_FFT_ROOTS[FFT_MAX + 1] = {1U, 998244352U, 86583718U, 509520358U, 337190230U, 87557064U, 609441965U, 135236158U, 304459705U, 685443576U, 381598368U, 335559352U, 129292727U, 358024708U, 814576206U, 708402881U, 283043518U, 3707709U, 121392023U, 704923114U, 950391366U, 428961804U, 382752275U, 469870224U};
constexpr Mint FFT_RATIOS[FFT_MAX] = {911660635U, 509520358U, 369330050U, 332049552U, 983190778U, 123842337U, 238493703U, 975955924U, 603855026U, 856644456U, 131300601U, 842657263U, 730768835U, 942482514U, 806263778U, 151565301U, 510815449U, 503497456U, 743006876U, 741047443U, 56250497U, 867605899U};
constexpr Mint INV_FFT_RATIOS[FFT_MAX] = {86583718U, 372528824U, 373294451U, 645684063U, 112220581U, 692852209U, 155456985U, 797128860U, 90816748U, 860285882U, 927414960U, 354738543U, 109331171U, 293255632U, 535113200U, 308540755U, 121186627U, 608385704U, 438932459U, 359477183U, 824071951U, 103369235U};
// as[rev(i)] <- \sum_j \zeta^(ij) as[j]
void fft(Mint *as, int n)
{
assert(!(n & (n - 1)));
assert(1 <= n);
assert(n <= 1 << FFT_MAX);
int m = n;
if (m >>= 1)
{
for (int i = 0; i < m; ++i)
{
const unsigned x = as[i + m].x; // < MO
as[i + m].x = as[i].x + MO - x; // < 2 MO
as[i].x += x; // < 2 MO
}
}
if (m >>= 1)
{
Mint prod = 1U;
for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1))
{
for (int i = i0; i < i0 + m; ++i)
{
const unsigned x = (prod * as[i + m]).x; // < MO
as[i + m].x = as[i].x + MO - x; // < 3 MO
as[i].x += x; // < 3 MO
}
prod *= FFT_RATIOS[__builtin_ctz(++h)];
}
}
for (; m;)
{
if (m >>= 1)
{
Mint prod = 1U;
for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1))
{
for (int i = i0; i < i0 + m; ++i)
{
const unsigned x = (prod * as[i + m]).x; // < MO
as[i + m].x = as[i].x + MO - x; // < 4 MO
as[i].x += x; // < 4 MO
}
prod *= FFT_RATIOS[__builtin_ctz(++h)];
}
}
if (m >>= 1)
{
Mint prod = 1U;
for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1))
{
for (int i = i0; i < i0 + m; ++i)
{
const unsigned x = (prod * as[i + m]).x; // < MO
as[i].x = (as[i].x >= MO2) ? (as[i].x - MO2) : as[i].x; // < 2 MO
as[i + m].x = as[i].x + MO - x; // < 3 MO
as[i].x += x; // < 3 MO
}
prod *= FFT_RATIOS[__builtin_ctz(++h)];
}
}
}
for (int i = 0; i < n; ++i)
{
as[i].x = (as[i].x >= MO2) ? (as[i].x - MO2) : as[i].x; // < 2 MO
as[i].x = (as[i].x >= MO) ? (as[i].x - MO) : as[i].x; // < MO
}
}
// as[i] <- (1/n) \sum_j \zeta^(-ij) as[rev(j)]
void invFft(Mint *as, int n)
{
assert(!(n & (n - 1)));
assert(1 <= n);
assert(n <= 1 << FFT_MAX);
int m = 1;
if (m < n >> 1)
{
Mint prod = 1U;
for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1))
{
for (int i = i0; i < i0 + m; ++i)
{
const unsigned long long y = as[i].x + MO - as[i + m].x; // < 2 MO
as[i].x += as[i + m].x; // < 2 MO
as[i + m].x = (prod.x * y) % MO; // < MO
}
prod *= INV_FFT_RATIOS[__builtin_ctz(++h)];
}
m <<= 1;
}
for (; m < n >> 1; m <<= 1)
{
Mint prod = 1U;
for (int h = 0, i0 = 0; i0 < n; i0 += (m << 1))
{
for (int i = i0; i < i0 + (m >> 1); ++i)
{
const unsigned long long y = as[i].x + MO2 - as[i + m].x; // < 4 MO
as[i].x += as[i + m].x; // < 4 MO
as[i].x = (as[i].x >= MO2) ? (as[i].x - MO2) : as[i].x; // < 2 MO
as[i + m].x = (prod.x * y) % MO; // < MO
}
for (int i = i0 + (m >> 1); i < i0 + m; ++i)
{
const unsigned long long y = as[i].x + MO - as[i + m].x; // < 2 MO
as[i].x += as[i + m].x; // < 2 MO
as[i + m].x = (prod.x * y) % MO; // < MO
}
prod *= INV_FFT_RATIOS[__builtin_ctz(++h)];
}
}
if (m < n)
{
for (int i = 0; i < m; ++i)
{
const unsigned y = as[i].x + MO2 - as[i + m].x; // < 4 MO
as[i].x += as[i + m].x; // < 4 MO
as[i + m].x = y; // < 4 MO
}
}
const Mint invN = Mint(n).inv();
for (int i = 0; i < n; ++i)
{
as[i] *= invN;
}
}
void fft(vector<Mint> &as)
{
fft(as.data(), as.size());
}
void invFft(vector<Mint> &as)
{
invFft(as.data(), as.size());
}
vector<Mint> convolve(vector<Mint> as, vector<Mint> bs)
{
if (as.empty() || bs.empty())
return {};
const int len = as.size() + bs.size() - 1;
int n = 1;
for (; n < len; n <<= 1)
{
}
as.resize(n);
fft(as);
bs.resize(n);
fft(bs);
for (int i = 0; i < n; ++i)
as[i] *= bs[i];
invFft(as);
as.resize(len);
return as;
}
vector<Mint> square(vector<Mint> as)
{
if (as.empty())
return {};
const int len = as.size() + as.size() - 1;
int n = 1;
for (; n < len; n <<= 1)
{
}
as.resize(n);
fft(as);
for (int i = 0; i < n; ++i)
as[i] *= as[i];
invFft(as);
as.resize(len);
return as;
}
////////////////////////////////////////////////////////////////////////////////
#endif // LIBRA_ALGEBRA_FFT_998244353_H_
using std::max;
using std::min;
using std::vector;
////////////////////////////////////////////////////////////////////////////////
// inv: log, exp, pow
// fac: shift
// invFac: shift
constexpr int LIM_INV = 1 << 20; // @
Mint inv[LIM_INV], fac[LIM_INV], invFac[LIM_INV];
struct ModIntPreparator
{
ModIntPreparator()
{
inv[1] = 1;
for (int i = 2; i < LIM_INV; ++i)
inv[i] = -((Mint::M / i) * inv[Mint::M % i]);
fac[0] = 1;
for (int i = 1; i < LIM_INV; ++i)
fac[i] = fac[i - 1] * i;
invFac[0] = 1;
for (int i = 1; i < LIM_INV; ++i)
invFac[i] = invFac[i - 1] * inv[i];
}
} preparator;
// polyWork0: *, inv, div, divAt, log, exp, pow, sqrt, shift
// polyWork1: inv, div, divAt, log, exp, pow, sqrt, shift
// polyWork2: divAt, exp, pow, sqrt
// polyWork3: exp, pow, sqrt
static constexpr int LIM_POLY = 1 << 20; // @
static_assert(LIM_POLY <= 1 << FFT_MAX, "Poly: LIM_POLY <= 1 << FFT_MAX must hold.");
static Mint polyWork0[LIM_POLY], polyWork1[LIM_POLY], polyWork2[LIM_POLY], polyWork3[LIM_POLY];
struct Poly : public vector<Mint>
{
Poly() {}
explicit Poly(int n) : vector<Mint>(n) {}
Poly(const vector<Mint> &vec) : vector<Mint>(vec) {}
Poly(std::initializer_list<Mint> il) : vector<Mint>(il) {}
int size() const { return vector<Mint>::size(); }
Mint at(long long k) const { return (0 <= k && k < size()) ? (*this)[k] : 0U; }
int ord() const
{
for (int i = 0; i < size(); ++i)
if ((*this)[i])
return i;
return -1;
}
int deg() const
{
for (int i = size(); --i >= 0;)
if ((*this)[i])
return i;
return -1;
}
Poly mod(int n) const { return Poly(vector<Mint>(data(), data() + min(n, size()))); }
/*
friend std::ostream &operator<<(std::ostream &os, const Poly &fs)
{
os << "[";
for (int i = 0; i < fs.size(); ++i)
{
if (i > 0)
os << ", ";
os << fs[i];
}
return os << "]";
}
*/
Poly &operator+=(const Poly &fs)
{
if (size() < fs.size())
resize(fs.size());
for (int i = 0; i < fs.size(); ++i)
(*this)[i] += fs[i];
return *this;
}
Poly &operator-=(const Poly &fs)
{
if (size() < fs.size())
resize(fs.size());
for (int i = 0; i < fs.size(); ++i)
(*this)[i] -= fs[i];
return *this;
}
// 3 E(|t| + |f|)
Poly &operator*=(const Poly &fs)
{
if (empty() || fs.empty())
return *this = {};
const int nt = size(), nf = fs.size();
int n = 1;
for (; n < nt + nf - 1; n <<= 1)
{
}
assert(n <= LIM_POLY);
resize(n);
fft(data(), n); // 1 E(n)
memcpy(polyWork0, fs.data(), nf * sizeof(Mint));
memset(polyWork0 + nf, 0, (n - nf) * sizeof(Mint));
fft(polyWork0, n); // 1 E(n)
for (int i = 0; i < n; ++i)
(*this)[i] *= polyWork0[i];
invFft(data(), n); // 1 E(n)
resize(nt + nf - 1);
return *this;
}
// 13 E(deg(t) - deg(f) + 1)
// rev(t) = rev(f) rev(q) + x^(deg(t)-deg(f)+1) rev(r)
Poly &operator/=(const Poly &fs)
{
const int m = deg(), n = fs.deg();
assert(n != -1);
if (m < n)
return *this = {};
Poly tsRev(m - n + 1), fsRev(min(m - n, n) + 1);
for (int i = 0; i <= m - n; ++i)
tsRev[i] = (*this)[m - i];
for (int i = 0, i0 = min(m - n, n); i <= i0; ++i)
fsRev[i] = fs[n - i];
const Poly qsRev = tsRev.div(fsRev, m - n + 1); // 13 E(m - n + 1)
resize(m - n + 1);
for (int i = 0; i <= m - n; ++i)
(*this)[i] = qsRev[m - n - i];
return *this;
}
// 13 E(deg(t) - deg(f) + 1) + 3 E(|t|)
Poly &operator%=(const Poly &fs)
{
const Poly qs = *this / fs; // 13 E(deg(t) - deg(f) + 1)
*this -= fs * qs; // 3 E(|t|)
resize(deg() + 1);
return *this;
}
Poly &operator*=(const Mint &a)
{
for (int i = 0; i < size(); ++i)
(*this)[i] *= a;
return *this;
}
Poly &operator/=(const Mint &a)
{
const Mint b = a.inv();
for (int i = 0; i < size(); ++i)
(*this)[i] *= b;
return *this;
}
Poly operator+() const { return *this; }
Poly operator-() const
{
Poly fs(size());
for (int i = 0; i < size(); ++i)
fs[i] = -(*this)[i];
return fs;
}
Poly operator+(const Poly &fs) const { return (Poly(*this) += fs); }
Poly operator-(const Poly &fs) const { return (Poly(*this) -= fs); }
Poly operator*(const Poly &fs) const { return (Poly(*this) *= fs); }
Poly operator/(const Poly &fs) const { return (Poly(*this) /= fs); }
Poly operator%(const Poly &fs) const { return (Poly(*this) %= fs); }
Poly operator*(const Mint &a) const { return (Poly(*this) *= a); }
Poly operator/(const Mint &a) const { return (Poly(*this) /= a); }
friend Poly operator*(const Mint &a, const Poly &fs) { return fs * a; }
// 10 E(n)
// f <- f - (t f - 1) f
Poly inv(int n) const
{
assert(!empty());
assert((*this)[0]);
assert(1 <= n);
assert(n == 1 || 1 << (32 - __builtin_clz(n - 1)) <= LIM_POLY);
Poly fs(n);
fs[0] = (*this)[0].inv();
for (int m = 1; m < n; m <<= 1)
{
memcpy(polyWork0, data(), min(m << 1, size()) * sizeof(Mint));
memset(polyWork0 + min(m << 1, size()), 0, ((m << 1) - min(m << 1, size())) * sizeof(Mint));
fft(polyWork0, m << 1); // 2 E(n)
memcpy(polyWork1, fs.data(), min(m << 1, n) * sizeof(Mint));
memset(polyWork1 + min(m << 1, n), 0, ((m << 1) - min(m << 1, n)) * sizeof(Mint));
fft(polyWork1, m << 1); // 2 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m << 1); // 2 E(n)
memset(polyWork0, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 2 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m << 1); // 2 E(n)
for (int i = m, i0 = min(m << 1, n); i < i0; ++i)
fs[i] = -polyWork0[i];
}
return fs;
}
// 9 E(n)
// Need (4 m)-th roots of unity to lift from (mod x^m) to (mod x^(2m)).
// f <- f - (t f - 1) f
// (t f^2) mod ((x^(2m) - 1) (x^m - 1^(1/4)))
/*
Poly inv(int n) const {
assert(!empty()); assert((*this)[0]); assert(1 <= n);
assert(n == 1 || 3 << (31 - __builtin_clz(n - 1)) <= LIM_POLY);
assert(n <= 1 << (FFT_MAX - 1));
Poly fs(n);
fs[0] = (*this)[0].inv();
for (int h = 2, m = 1; m < n; ++h, m <<= 1) {
const Mint a = FFT_ROOTS[h], b = INV_FFT_ROOTS[h];
memcpy(polyWork0, data(), min(m << 1, size()) * sizeof(Mint));
memset(polyWork0 + min(m << 1, size()), 0, ((m << 1) - min(m << 1, size())) * sizeof(Mint));
{
Mint aa = 1;
for (int i = 0; i < m; ++i) { polyWork0[(m << 1) + i] = aa * polyWork0[i]; aa *= a; }
for (int i = 0; i < m; ++i) { polyWork0[(m << 1) + i] += aa * polyWork0[m + i]; aa *= a; }
}
fft(polyWork0, m << 1); // 2 E(n)
fft(polyWork0 + (m << 1), m); // 1 E(n)
memcpy(polyWork1, fs.data(), min(m << 1, n) * sizeof(Mint));
memset(polyWork1 + min(m << 1, n), 0, ((m << 1) - min(m << 1, n)) * sizeof(Mint));
{
Mint aa = 1;
for (int i = 0; i < m; ++i) { polyWork1[(m << 1) + i] = aa * polyWork1[i]; aa *= a; }
for (int i = 0; i < m; ++i) { polyWork1[(m << 1) + i] += aa * polyWork1[m + i]; aa *= a; }
}
fft(polyWork1, m << 1); // 2 E(n)
fft(polyWork1 + (m << 1), m); // 1 E(n)
for (int i = 0; i < (m << 1) + m; ++i) polyWork0[i] *= polyWork1[i] * polyWork1[i];
invFft(polyWork0, m << 1); // 2 E(n)
invFft(polyWork0 + (m << 1), m); // 1 E(n)
// 2 f0 + (-f2), (-f1) + (-f3), 1^(1/4) (-f1) - (-f2) - 1^(1/4) (-f3)
{
Mint bb = 1;
for (int i = 0, i0 = min(m, n - m); i < i0; ++i) {
unsigned x = polyWork0[i].x + (bb * polyWork0[(m << 1) + i]).x + MO2 - (fs[i].x << 1); // < 4 MO
fs[m + i] = Mint(static_cast<unsigned long long>(FFT_ROOTS[2].x) * x) - polyWork0[m + i];
fs[m + i].x = ((fs[m + i].x & 1) ? (fs[m + i].x + MO) : fs[m + i].x) >> 1;
bb *= b;
}
}
}
return fs;
}
*/
// 13 E(n)
// g = (1 / f) mod x^m
// h <- h - (f h - t) g
Poly div(const Poly &fs, int n) const
{
assert(!fs.empty());
assert(fs[0]);
assert(1 <= n);
if (n == 1)
return {at(0) / fs[0]};
// m < n <= 2 m
const int m = 1 << (31 - __builtin_clz(n - 1));
assert(m << 1 <= LIM_POLY);
Poly gs = fs.inv(m); // 5 E(n)
gs.resize(m << 1);
fft(gs.data(), m << 1); // 1 E(n)
memcpy(polyWork0, data(), min(m, size()) * sizeof(Mint));
memset(polyWork0 + min(m, size()), 0, ((m << 1) - min(m, size())) * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= gs[i];
invFft(polyWork0, m << 1); // 1 E(n)
Poly hs(n);
memcpy(hs.data(), polyWork0, m * sizeof(Mint));
memset(polyWork0 + m, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
memcpy(polyWork1, fs.data(), min(m << 1, fs.size()) * sizeof(Mint));
memset(polyWork1 + min(m << 1, fs.size()), 0, ((m << 1) - min(m << 1, fs.size())) * sizeof(Mint));
fft(polyWork1, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m << 1); // 1 E(n)
memset(polyWork0, 0, m * sizeof(Mint));
for (int i = m, i0 = min(m << 1, size()); i < i0; ++i)
polyWork0[i] -= (*this)[i];
fft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= gs[i];
invFft(polyWork0, m << 1); // 1 E(n)
for (int i = m; i < n; ++i)
hs[i] = -polyWork0[i];
return hs;
}
// (4 (floor(log_2 k) - ceil(log_2 |f|)) + 16) E(|f|) for |t| < |f|
// [x^k] (t(x) / f(x)) = [x^k] ((t(x) f(-x)) / (f(x) f(-x))
// polyWork0: half of (2 m)-th roots of unity, inversed, bit-reversed
Mint divAt(const Poly &fs, long long k) const
{
assert(k >= 0);
if (size() >= fs.size())
{
const Poly qs = *this / fs; // 13 E(deg(t) - deg(f) + 1)
Poly rs = *this - fs * qs; // 3 E(|t|)
rs.resize(rs.deg() + 1);
return qs.at(k) + rs.divAt(fs, k);
}
int h = 0, m = 1;
for (; m < fs.size(); ++h, m <<= 1)
{
}
if (k < m)
{
const Poly gs = fs.inv(k + 1); // 10 E(|f|)
Mint sum;
for (int i = 0, i0 = min<int>(k + 1, size()); i < i0; ++i)
sum += (*this)[i] * gs[k - i];
return sum;
}
assert(m << 1 <= LIM_POLY);
polyWork0[0] = Mint(2U).inv();
for (int hh = 0; hh < h; ++hh)
for (int i = 0; i < 1 << hh; ++i)
polyWork0[1 << hh | i] = polyWork0[i] * INV_FFT_ROOTS[hh + 2];
const Mint a = FFT_ROOTS[h + 1];
memcpy(polyWork2, data(), size() * sizeof(Mint));
memset(polyWork2 + size(), 0, ((m << 1) - size()) * sizeof(Mint));
fft(polyWork2, m << 1); // 2 E(|f|)
memcpy(polyWork1, fs.data(), fs.size() * sizeof(Mint));
memset(polyWork1 + fs.size(), 0, ((m << 1) - fs.size()) * sizeof(Mint));
fft(polyWork1, m << 1); // 2 E(|f|)
for (;;)
{
if (k & 1)
{
for (int i = 0; i < m; ++i)
polyWork2[i] = polyWork0[i] * (polyWork2[i << 1 | 0] * polyWork1[i << 1 | 1] - polyWork2[i << 1 | 1] * polyWork1[i << 1 | 0]);
}
else
{
for (int i = 0; i < m; ++i)
{
polyWork2[i] = polyWork2[i << 1 | 0] * polyWork1[i << 1 | 1] + polyWork2[i << 1 | 1] * polyWork1[i << 1 | 0];
polyWork2[i].x = ((polyWork2[i].x & 1) ? (polyWork2[i].x + MO) : polyWork2[i].x) >> 1;
}
}
for (int i = 0; i < m; ++i)
polyWork1[i] = polyWork1[i << 1 | 0] * polyWork1[i << 1 | 1];
if ((k >>= 1) < m)
{
invFft(polyWork2, m); // 1 E(|f|)
invFft(polyWork1, m); // 1 E(|f|)
// Poly::inv does not use polyWork2
const Poly gs = Poly(vector<Mint>(polyWork1, polyWork1 + k + 1)).inv(k + 1); // 10 E(|f|)
Mint sum;
for (int i = 0; i <= k; ++i)
sum += polyWork2[i] * gs[k - i];
return sum;
}
memcpy(polyWork2 + m, polyWork2, m * sizeof(Mint));
invFft(polyWork2 + m, m); // (floor(log_2 k) - ceil(log_2 |f|)) E(|f|)
memcpy(polyWork1 + m, polyWork1, m * sizeof(Mint));
invFft(polyWork1 + m, m); // (floor(log_2 k) - ceil(log_2 |f|)) E(|f|)
Mint aa = 1;
for (int i = m; i < m << 1; ++i)
{
polyWork2[i] *= aa;
polyWork1[i] *= aa;
aa *= a;
}
fft(polyWork2 + m, m); // (floor(log_2 k) - ceil(log_2 |f|)) E(|f|)
fft(polyWork1 + m, m); // (floor(log_2 k) - ceil(log_2 |f|)) E(|f|)
}
}
// 13 E(n)
// D log(t) = (D t) / t
Poly log(int n) const
{
assert(!empty());
assert((*this)[0].x == 1U);
assert(n <= LIM_INV);
Poly fs = mod(n);
for (int i = 0; i < fs.size(); ++i)
fs[i] *= i;
fs = fs.div(*this, n);
for (int i = 1; i < n; ++i)
fs[i] *= ::inv[i];
return fs;
}
// (16 + 1/2) E(n)
// f = exp(t) mod x^m ==> (D f) / f == D t (mod x^m)
// g = (1 / exp(t)) mod x^m
// f <- f - (log f - t) / (1 / f)
// = f - (I ((D f) / f) - t) f
// == f - (I ((D f) / f + (f g - 1) ((D f) / f - D (t mod x^m))) - t) f (mod x^(2m))
// = f - (I (g (D f - f D (t mod x^m)) + D (t mod x^m)) - t) f
// g <- g - (f g - 1) g
// polyWork1: DFT(f, 2 m), polyWork2: g, polyWork3: DFT(g, 2 m)
Poly exp(int n) const
{
assert(!empty());
assert(!(*this)[0]);
assert(1 <= n);
assert(n == 1 || 1 << (32 - __builtin_clz(n - 1)) <= min(LIM_INV, LIM_POLY));
if (n == 1)
return {1U};
if (n == 2)
return {1U, at(1)};
Poly fs(n);
fs[0].x = polyWork1[0].x = polyWork1[1].x = polyWork2[0].x = 1U;
int m;
for (m = 1; m << 1 < n; m <<= 1)
{
for (int i = 0, i0 = min(m, size()); i < i0; ++i)
polyWork0[i] = i * (*this)[i];
memset(polyWork0 + min(m, size()), 0, (m - min(m, size())) * sizeof(Mint));
fft(polyWork0, m); // (1/2) E(n)
for (int i = 0; i < m; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m); // (1/2) E(n)
for (int i = 0; i < m; ++i)
polyWork0[i] -= i * fs[i];
memset(polyWork0 + m, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
memcpy(polyWork3, polyWork2, m * sizeof(Mint));
memset(polyWork3 + m, 0, m * sizeof(Mint));
fft(polyWork3, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork3[i];
invFft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m; ++i)
polyWork0[i] *= ::inv[m + i];
for (int i = 0, i0 = min(m, size() - m); i < i0; ++i)
polyWork0[i] += (*this)[m + i];
memset(polyWork0 + m, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m << 1); // 1 E(n)
memcpy(fs.data() + m, polyWork0, m * sizeof(Mint));
memcpy(polyWork1, fs.data(), (m << 1) * sizeof(Mint));
memset(polyWork1 + (m << 1), 0, (m << 1) * sizeof(Mint));
fft(polyWork1, m << 2); // 2 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] = polyWork1[i] * polyWork3[i];
invFft(polyWork0, m << 1); // 1 E(n)
memset(polyWork0, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork3[i];
invFft(polyWork0, m << 1); // 1 E(n)
for (int i = m; i < m << 1; ++i)
polyWork2[i] = -polyWork0[i];
}
for (int i = 0, i0 = min(m, size()); i < i0; ++i)
polyWork0[i] = i * (*this)[i];
memset(polyWork0 + min(m, size()), 0, (m - min(m, size())) * sizeof(Mint));
fft(polyWork0, m); // (1/2) E(n)
for (int i = 0; i < m; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m); // (1/2) E(n)
for (int i = 0; i < m; ++i)
polyWork0[i] -= i * fs[i];
memcpy(polyWork0 + m, polyWork0 + (m >> 1), (m >> 1) * sizeof(Mint));
memset(polyWork0 + (m >> 1), 0, (m >> 1) * sizeof(Mint));
memset(polyWork0 + m + (m >> 1), 0, (m >> 1) * sizeof(Mint));
fft(polyWork0, m); // (1/2) E(n)
fft(polyWork0 + m, m); // (1/2) E(n)
memcpy(polyWork3 + m, polyWork2 + (m >> 1), (m >> 1) * sizeof(Mint));
memset(polyWork3 + m + (m >> 1), 0, (m >> 1) * sizeof(Mint));
fft(polyWork3 + m, m); // (1/2) E(n)
for (int i = 0; i < m; ++i)
polyWork0[m + i] = polyWork0[i] * polyWork3[m + i] + polyWork0[m + i] * polyWork3[i];
for (int i = 0; i < m; ++i)
polyWork0[i] *= polyWork3[i];
invFft(polyWork0, m); // (1/2) E(n)
invFft(polyWork0 + m, m); // (1/2) E(n)
for (int i = 0; i < m >> 1; ++i)
polyWork0[(m >> 1) + i] += polyWork0[m + i];
for (int i = 0; i < m; ++i)
polyWork0[i] *= ::inv[m + i];
for (int i = 0, i0 = min(m, size() - m); i < i0; ++i)
polyWork0[i] += (*this)[m + i];
memset(polyWork0 + m, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m << 1); // 1 E(n)
memcpy(fs.data() + m, polyWork0, (n - m) * sizeof(Mint));
return fs;
}
// (29 + 1/2) E(n)
// g <- g - (log g - a log t) g
Poly pow(Mint a, int n) const
{
assert(!empty());
assert((*this)[0].x == 1U);
assert(1 <= n);
return (a * log(n)).exp(n); // 13 E(n) + (16 + 1/2) E(n)
}
// (29 + 1/2) E(n - a ord(t))
Poly pow(long long a, int n) const
{
assert(a >= 0);
assert(1 <= n);
if (a == 0)
{
Poly gs(n);
gs[0].x = 1U;
return gs;
}
const int o = ord();
if (o == -1 || o > (n - 1) / a)
return Poly(n);
const Mint b = (*this)[o].inv(), c = (*this)[o].pow(a);
const int ntt = min<int>(n - a * o, size() - o);
Poly tts(ntt);
for (int i = 0; i < ntt; ++i)
tts[i] = b * (*this)[o + i];
tts = tts.pow(Mint(a), n - a * o); // (29 + 1/2) E(n - a ord(t))
Poly gs(n);
for (int i = 0; i < n - a * o; ++i)
gs[a * o + i] = c * tts[i];
return gs;
}
// (10 + 1/2) E(n)
// f = t^(1/2) mod x^m, g = 1 / t^(1/2) mod x^m
// f <- f - (f^2 - h) g / 2
// g <- g - (f g - 1) g
// polyWork1: DFT(f, m), polyWork2: g, polyWork3: DFT(g, 2 m)
Poly sqrt(int n) const
{
assert(!empty());
assert((*this)[0].x == 1U);
assert(1 <= n);
assert(n == 1 || 1 << (32 - __builtin_clz(n - 1)) <= LIM_POLY);
if (n == 1)
return {1U};
if (n == 2)
return {1U, at(1) / 2};
Poly fs(n);
fs[0].x = polyWork1[0].x = polyWork2[0].x = 1U;
int m;
for (m = 1; m << 1 < n; m <<= 1)
{
for (int i = 0; i < m; ++i)
polyWork1[i] *= polyWork1[i];
invFft(polyWork1, m); // (1/2) E(n)
for (int i = 0, i0 = min(m, size()); i < i0; ++i)
polyWork1[i] -= (*this)[i];
for (int i = 0, i0 = min(m, size() - m); i < i0; ++i)
polyWork1[i] -= (*this)[m + i];
memset(polyWork1 + m, 0, m * sizeof(Mint));
fft(polyWork1, m << 1); // 1 E(n)
memcpy(polyWork3, polyWork2, m * sizeof(Mint));
memset(polyWork3 + m, 0, m * sizeof(Mint));
fft(polyWork3, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork1[i] *= polyWork3[i];
invFft(polyWork1, m << 1); // 1 E(n)
for (int i = 0; i < m; ++i)
{
polyWork1[i] = -polyWork1[i];
fs[m + i].x = ((polyWork1[i].x & 1) ? (polyWork1[i].x + MO) : polyWork1[i].x) >> 1;
}
memcpy(polyWork1, fs.data(), (m << 1) * sizeof(Mint));
fft(polyWork1, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] = polyWork1[i] * polyWork3[i];
invFft(polyWork0, m << 1); // 1 E(n)
memset(polyWork0, 0, m * sizeof(Mint));
fft(polyWork0, m << 1); // 1 E(n)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork3[i];
invFft(polyWork0, m << 1); // 1 E(n)
for (int i = m; i < m << 1; ++i)
polyWork2[i] = -polyWork0[i];
}
for (int i = 0; i < m; ++i)
polyWork1[i] *= polyWork1[i];
invFft(polyWork1, m); // (1/2) E(n)
for (int i = 0, i0 = min(m, size()); i < i0; ++i)
polyWork1[i] -= (*this)[i];
for (int i = 0, i0 = min(m, size() - m); i < i0; ++i)
polyWork1[i] -= (*this)[m + i];
memcpy(polyWork1 + m, polyWork1 + (m >> 1), (m >> 1) * sizeof(Mint));
memset(polyWork1 + (m >> 1), 0, (m >> 1) * sizeof(Mint));
memset(polyWork1 + m + (m >> 1), 0, (m >> 1) * sizeof(Mint));
fft(polyWork1, m); // (1/2) E(n)
fft(polyWork1 + m, m); // (1/2) E(n)
memcpy(polyWork3 + m, polyWork2 + (m >> 1), (m >> 1) * sizeof(Mint));
memset(polyWork3 + m + (m >> 1), 0, (m >> 1) * sizeof(Mint));
fft(polyWork3 + m, m); // (1/2) E(n)
// for (int i = 0; i < m << 1; ++i) polyWork1[i] *= polyWork3[i];
for (int i = 0; i < m; ++i)
polyWork1[m + i] = polyWork1[i] * polyWork3[m + i] + polyWork1[m + i] * polyWork3[i];
for (int i = 0; i < m; ++i)
polyWork1[i] *= polyWork3[i];
invFft(polyWork1, m); // (1/2) E(n)
invFft(polyWork1 + m, m); // (1/2) E(n)
for (int i = 0; i < m >> 1; ++i)
polyWork1[(m >> 1) + i] += polyWork1[m + i];
for (int i = 0; i < n - m; ++i)
{
polyWork1[i] = -polyWork1[i];
fs[m + i].x = ((polyWork1[i].x & 1) ? (polyWork1[i].x + MO) : polyWork1[i].x) >> 1;
}
return fs;
}
// (10 + 1/2) E(n)
// modSqrt must return a quadratic residue if exists, or anything otherwise.
// Return {} if *this does not have a square root.
template <class F>
Poly sqrt(int n, F modSqrt) const
{
assert(1 <= n);
const int o = ord();
if (o == -1)
return Poly(n);
if (o & 1)
return {};
const Mint c = modSqrt((*this)[o]);
if (c * c != (*this)[o])
return {};
if (o >> 1 >= n)
return Poly(n);
const Mint b = (*this)[o].inv();
const int ntt = min(n - (o >> 1), size() - o);
Poly tts(ntt);
for (int i = 0; i < ntt; ++i)
tts[i] = b * (*this)[o + i];
tts = tts.sqrt(n - (o >> 1)); // (10 + 1/2) E(n)
Poly gs(n);
for (int i = 0; i < n - (o >> 1); ++i)
gs[(o >> 1) + i] = c * tts[i];
return gs;
}
// 6 E(|t|)
// x -> x + a
Poly shift(const Mint &a) const
{
if (empty())
return {};
const int n = size();
int m = 1;
for (; m < n; m <<= 1)
{
}
for (int i = 0; i < n; ++i)
polyWork0[i] = fac[i] * (*this)[i];
memset(polyWork0 + n, 0, ((m << 1) - n) * sizeof(Mint));
fft(polyWork0, m << 1); // 2 E(|t|)
{
Mint aa = 1;
for (int i = 0; i < n; ++i)
{
polyWork1[n - 1 - i] = invFac[i] * aa;
aa *= a;
}
}
memset(polyWork1 + n, 0, ((m << 1) - n) * sizeof(Mint));
fft(polyWork1, m << 1); // 2 E(|t|)
for (int i = 0; i < m << 1; ++i)
polyWork0[i] *= polyWork1[i];
invFft(polyWork0, m << 1); // 2 E(|t|)
Poly fs(n);
for (int i = 0; i < n; ++i)
fs[i] = invFac[i] * polyWork0[n - 1 + i];
return fs;
}
};
Mint linearRecurrenceAt(const vector<Mint> &as, const vector<Mint> &cs, long long k)
{
assert(!cs.empty());
assert(cs[0]);
const int d = cs.size() - 1;
assert(as.size() >= static_cast<size_t>(d));
return (Poly(vector<Mint>(as.begin(), as.begin() + d)) * cs).mod(d).divAt(cs, k);
}
struct SubproductTree
{
int logN, n, nn;
vector<Mint> xs;
// [DFT_4((X-xs[0])(X-xs[1])(X-xs[2])(X-xs[3]))] [(X-xs[0])(X-xs[1])(X-xs[2])(X-xs[3])mod X^4]
// [ DFT_4((X-xs[0])(X-xs[1])) ] [ DFT_4((X-xs[2])(X-xs[3])) ]
// [ DFT_2(X-xs[0]) ] [ DFT_2(X-xs[1]) ] [ DFT_2(X-xs[2]) ] [ DFT_2(X-xs[3]) ]
vector<Mint> buf;
vector<Mint *> gss;
// (1 - xs[0] X) ... (1 - xs[nn-1] X)
Poly all;
// (ceil(log_2 n) + O(1)) E(n)
SubproductTree(const vector<Mint> &xs_)
{
n = xs_.size();
for (logN = 0, nn = 1; nn < n; ++logN, nn <<= 1)
{
}
xs.assign(nn, 0U);
memcpy(xs.data(), xs_.data(), n * sizeof(Mint));
buf.assign((logN + 1) * (nn << 1), 0U);
gss.assign(nn << 1, nullptr);
for (int h = 0; h <= logN; ++h)
for (int u = 1 << h; u < 1 << (h + 1); ++u)
{
gss[u] = buf.data() + (h * (nn << 1) + ((u - (1 << h)) << (logN - h + 1)));
}
for (int i = 0; i < nn; ++i)
{
gss[nn + i][0] = -xs[i] + 1;
gss[nn + i][1] = -xs[i] - 1;
}
if (nn == 1)
gss[1][1] += 2;
for (int h = logN; --h >= 0;)
{
const int m = 1 << (logN - h);
for (int u = 1 << (h + 1); --u >= 1 << h;)
{
for (int i = 0; i < m; ++i)
gss[u][i] = gss[u << 1][i] * gss[u << 1 | 1][i];
memcpy(gss[u] + m, gss[u], m * sizeof(Mint));
invFft(gss[u] + m, m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
if (h > 0)
{
gss[u][m] -= 2;
const Mint a = FFT_ROOTS[logN - h + 1];
Mint aa = 1;
for (int i = m; i < m << 1; ++i)
{
gss[u][i] *= aa;
aa *= a;
};
fft(gss[u] + m, m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
}
}
}
all.resize(nn + 1);
all[0] = 1;
for (int i = 1; i < nn; ++i)
all[i] = gss[1][nn + nn - i];
all[nn] = gss[1][nn] - 1;
}
// ((3/2) ceil(log_2 n) + O(1)) E(n) + 10 E(|f|) + 3 E(|f| + 2^(ceil(log_2 n)))
vector<Mint> multiEval(const Poly &fs) const
{
vector<Mint> work0(nn), work1(nn), work2(nn);
{
const int m = max(fs.size(), 1);
auto invAll = all.inv(m); // 10 E(|f|)
std::reverse(invAll.begin(), invAll.end());
int mm;
for (mm = 1; mm < m - 1 + nn; mm <<= 1)
{
}
invAll.resize(mm, 0U);
fft(invAll); // E(|f| + 2^(ceil(log_2 n)))
vector<Mint> ffs(mm, 0U);
memcpy(ffs.data(), fs.data(), fs.size() * sizeof(Mint));
fft(ffs); // E(|f| + 2^(ceil(log_2 n)))
for (int i = 0; i < mm; ++i)
ffs[i] *= invAll[i];
invFft(ffs); // E(|f| + 2^(ceil(log_2 n)))
memcpy(((logN & 1) ? work1 : work0).data(), ffs.data() + m - 1, nn * sizeof(Mint));
}
for (int h = 0; h < logN; ++h)
{
const int m = 1 << (logN - h);
for (int u = 1 << h; u < 1 << (h + 1); ++u)
{
Mint *hs = (((logN - h) & 1) ? work1 : work0).data() + ((u - (1 << h)) << (logN - h));
Mint *hs0 = (((logN - h) & 1) ? work0 : work1).data() + ((u - (1 << h)) << (logN - h));
Mint *hs1 = hs0 + (m >> 1);
fft(hs, m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
for (int i = 0; i < m; ++i)
work2[i] = gss[u << 1 | 1][i] * hs[i];
invFft(work2.data(), m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
memcpy(hs0, work2.data() + (m >> 1), (m >> 1) * sizeof(Mint));
for (int i = 0; i < m; ++i)
work2[i] = gss[u << 1][i] * hs[i];
invFft(work2.data(), m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
memcpy(hs1, work2.data() + (m >> 1), (m >> 1) * sizeof(Mint));
}
}
work0.resize(n);
return work0;
}
// ((5/2) ceil(log_2 n) + O(1)) E(n)
Poly interpolate(const vector<Mint> &ys) const
{
assert(static_cast<int>(ys.size()) == n);
Poly gs(n);
for (int i = 0; i < n; ++i)
gs[i] = (i + 1) * all[n - (i + 1)];
const vector<Mint> denoms = multiEval(gs); // ((3/2) ceil(log_2 n) + O(1)) E(n)
vector<Mint> work(nn << 1, 0U);
for (int i = 0; i < n; ++i)
{
// xs[0], ..., xs[n - 1] are not distinct
assert(denoms[i]);
work[i << 1] = work[i << 1 | 1] = ys[i] / denoms[i];
}
for (int h = logN; --h >= 0;)
{
const int m = 1 << (logN - h);
for (int u = 1 << (h + 1); --u >= 1 << h;)
{
Mint *hs = work.data() + ((u - (1 << h)) << (logN - h + 1));
for (int i = 0; i < m; ++i)
hs[i] = gss[u << 1 | 1][i] * hs[i] + gss[u << 1][i] * hs[m + i];
if (h > 0)
{
memcpy(hs + m, hs, m * sizeof(Mint));
invFft(hs + m, m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
const Mint a = FFT_ROOTS[logN - h + 1];
Mint aa = 1;
for (int i = m; i < m << 1; ++i)
{
hs[i] *= aa;
aa *= a;
};
fft(hs + m, m); // ((1/2) ceil(log_2 n) + O(1)) E(n)
}
}
}
invFft(work.data(), nn); // E(n)
return Poly(vector<Mint>(work.data() + nn - n, work.data() + nn));
}
};
int main()
{
int n = FastIO::rd() +1, m = FastIO::rd() + 1;
vector<Mint> a(n), b(m);
for (int i = 0; i < n; ++i)
a[i].x = FastIO::rd();
for (int i = 0; i < m; ++i)
b[i].x = FastIO::rd();
vector<Mint> res = convolve(a, b);
for (int i = 0; i < n + m - 1; ++i)
FastIO::wt(res[i].x, (i == n + m - 2) ? '\n' : ' ');
}
詳細信息
answer.code:4:10: fatal error: algorithm: No such file or directory #include <algorithm> ^~~~~~~~~~~ compilation terminated.