結果

問題 No.696 square1001 and Permutation 5
コンテスト
ユーザー heno239
提出日時 2023-04-07 19:18:46
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
WA  
実行時間 -
コード長 9,605 bytes
コンパイル時間 2,861 ms
コンパイル使用メモリ 176,292 KB
最終ジャッジ日時 2025-02-12 00:04:02
ジャッジサーバーID
（参考情報） 		judge3 / judge2
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 2
other AC * 9 WA * 3
権限があれば一括ダウンロードができます

ソースコード

diff # 

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<unordered_set>
#include<utility>
#include<cassert>
#include<complex>
#include<numeric>
#include<array>
#include<chrono>
using namespace std;

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
//ll mod = 1;
constexpr ll mod = 998244353;
//constexpr ll mod = 1000000007;
const ll INF = mod * mod;
typedef pair<int, int>P;

#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
#define all(v) (v).begin(),(v).end()
typedef pair<ll, ll> LP;

using ld = long double;
typedef pair<ld, ld> LDP;
const ld eps = 1e-2;
const ld pi = acosl(-1.0);

template<typename T>
void chmin(T& a, T b) {
	a = min(a, b);
}
template<typename T>
void chmax(T& a, T b) {
	a = max(a, b);
}
template<typename T>
vector<T> vmerge(vector<T>& a, vector<T>& b) {
	vector<T> res;
	int ida = 0, idb = 0;
	while (ida < a.size() || idb < b.size()) {
		if (idb == b.size()) {
			res.push_back(a[ida]); ida++;
		}
		else if (ida == a.size()) {
			res.push_back(b[idb]); idb++;
		}
		else {
			if (a[ida] < b[idb]) {
				res.push_back(a[ida]); ida++;
			}
			else {
				res.push_back(b[idb]); idb++;
			}
		}
	}
	return res;
}
template<typename T>
void cinarray(vector<T>& v) {
	rep(i, v.size())cin >> v[i];
}
template<typename T>
void coutarray(vector<T>& v) {
	rep(i, v.size()) {
		if (i > 0)cout << " "; cout << v[i];
	}
	cout << "\n";
}
ll mod_pow(ll x, ll n, ll m = mod) {
	if (n < 0) {
		ll res = mod_pow(x, -n, m);
		return mod_pow(res, m - 2, m);
	}
	if (abs(x) >= m)x %= m;
	if (x < 0)x += m;
	//if (x == 0)return 0;
	ll res = 1;
	while (n) {
		if (n & 1)res = res * x % m;
		x = x * x % m; n >>= 1;
	}
	return res;
}
//mod should be <2^31
struct modint {
	int n;
	modint() :n(0) { ; }
	modint(ll m) {
		if (m < 0 || mod <= m) {
			m %= mod; if (m < 0)m += mod;
		}
		n = m;
	}
	operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
bool operator<(modint a, modint b) { return a.n < b.n; }
modint operator+=(modint& a, modint b) { a.n += b.n; if (a.n >= mod)a.n -= (int)mod; return a; }
modint operator-=(modint& a, modint b) { a.n -= b.n; if (a.n < 0)a.n += (int)mod; return a; }
modint operator*=(modint& a, modint b) { a.n = ((ll)a.n * b.n) % mod; return a; }
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, ll n) {
	if (n == 0)return modint(1);
	modint res = (a * a) ^ (n / 2);
	if (n % 2)res = res * a;
	return res;
}

ll inv(ll a, ll p) {
	return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p);
}
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }
modint operator/=(modint& a, modint b) { a = a / b; return a; }
const int max_n = 1 << 20;
modint fact[max_n], factinv[max_n];
void init_f() {
	fact[0] = modint(1);
	for (int i = 0; i < max_n - 1; i++) {
		fact[i + 1] = fact[i] * modint(i + 1);
	}
	factinv[max_n - 1] = modint(1) / fact[max_n - 1];
	for (int i = max_n - 2; i >= 0; i--) {
		factinv[i] = factinv[i + 1] * modint(i + 1);
	}
}
modint comb(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[b] * factinv[a - b];
}
modint combP(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[a - b];
}

ll gcd(ll a, ll b) {
	a = abs(a); b = abs(b);
	if (a < b)swap(a, b);
	while (b) {
		ll r = a % b; a = b; b = r;
	}
	return a;
}
template<typename T>
void addv(vector<T>& v, int loc, T val) {
	if (loc >= v.size())v.resize(loc + 1, 0);
	v[loc] += val;
}
/*const int mn = 2000005;
bool isp[mn];
vector<int> ps;
void init() {
	fill(isp + 2, isp + mn, true);
	for (int i = 2; i < mn; i++) {
		if (!isp[i])continue;
		ps.push_back(i);
		for (int j = 2 * i; j < mn; j += i) {
			isp[j] = false;
		}
	}
}*/

//[,val)
template<typename T>
auto prev_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	if (res == st.begin())return st.end();
	res--; return res;
}

//[val,)
template<typename T>
auto next_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	return res;
}
using mP = pair<modint, modint>;
mP operator+(mP a, mP b) {
	return { a.first + b.first,a.second + b.second };
}
mP operator+=(mP& a, mP b) {
	a = a + b; return a;
}
mP operator-(mP a, mP b) {
	return { a.first - b.first,a.second - b.second };
}
mP operator-=(mP& a, mP b) {
	a = a - b; return a;
}
LP operator+(LP a, LP b) {
	return { a.first + b.first,a.second + b.second };
}
LP operator+=(LP& a, LP b) {
	a = a + b; return a;
}
LP operator-(LP a, LP b) {
	return { a.first - b.first,a.second - b.second };
}
LP operator-=(LP& a, LP b) {
	a = a - b; return a;
}

mt19937 mt(time(0));

const string drul = "DRUL";
string senw = "SENW";
//DRUL,or SENW
//int dx[4] = { 1,0,-1,0 };
//int dy[4] = { 0,1,0,-1 };

//-----------------------------------------

template<typename T>
struct BIT {
private:
	vector<T> node; int n;
public:
	BIT(int n_) {
		n = n_; node.resize(n, 0);
	}
	//0-indexed
	void add(int a, T w) {
		for (int i = a; i < n; i |= i + 1)node[i] += w;
	}
	//[0,a)
	T sum(int a) {
		T ret = 0;
		for (int i = a - 1; i >= 0; i = (i & (i + 1)) - 1)ret += node[i];
		return ret;
	}
	//[a,b)
	T sum(int a, int b) {
		return sum(b) - sum(a);
	}
};


LDP operator*(const LDP& a, const LDP& b) {
	return LDP{ a.first * b.first - a.second * b.second , a.first * b.second + a.second * b.first };
}
LDP operator+(const LDP& a, const LDP& b) {
	return LDP{ a.first + b.first,a.second + b.second };
}
LDP operator-(const LDP& a, const LDP& b) {
	return LDP{ a.first - b.first,a.second - b.second };
}
//非再帰
//eps=0.01を忘れずに
typedef vector<LDP> poly;
poly dft(poly f, bool inverse = false) {
	int n = f.size(); int i, j, k;
	//bit左右反転
	for (i = 0, j = 1; j < n - 1; j++) {
		for (k = n >> 1; k > (i ^= k); k >>= 1);
		if (i > j)swap(f[i], f[j]);
	}
	for (int m = 2; m <= n; m *= 2) {
		LDP zeta = { cos(2 * pi / (ld)m), sin(2 * pi / (ld)m) };
		if (inverse) {
			zeta = { cos(2 * pi * (m - 1) / (ld)m), sin(2 * pi * (m - 1) / (ld)m) };
		}
		for (i = 0; i < n; i += m) {
			LDP powzeta = { 1,0 };
			for (k = i; k < i + m / 2; k++) {
				LDP t1 = f[k], t2 = powzeta * f[k + m / 2];
				f[k] = t1 + t2; f[k + m / 2] = t1 - t2;
				powzeta = powzeta * zeta;
			}
		}
	}
	if (inverse) {
		for (i = 0; i < n; i++) {
			f[i].first /= (ld)n;
			f[i].second /= (ld)n;
		}
	}
	return f;
}
poly multiply(poly g, poly h) {
	if (min(g.size(), h.size()) <= 60) {
		poly res(g.size() + h.size() - 1);
		rep(i, g.size())rep(j, h.size()) {
			res[i + j] = res[i+j]+g[i] * h[j];
		}
		return res;
	}
	int n = 1; int sz = g.size() + h.size();
	while (n <= sz)n *= 2;
	while (g.size() < n) {
		g.push_back({ 0,0 });
	}
	while (h.size() < n) {
		h.push_back({ 0,0 });
	}
	poly gg = dft(g);
	poly hh = dft(h);
	poly ff;
	rep(i, n) {
		ff.push_back(gg[i] * hh[i]);
	}
	return dft(ff, true);
}


const ll mm = 1000000;
struct Data {
	vector<ll> v0, v1;
	void init(P p) {
		v0.push_back(p.first);
		v1.push_back(p.second);
	}
};
void normalize(vector<ll> &v) {
	rep(i, v.size()) {
		ll d = v[i] / mm;
		v[i] %= mm;
		if (d > 0) {
			if (i + 1 == v.size()) {
				v.push_back(d);
			}
			else {
				v[i + 1] += d;
			}
		}
	}
	while (v.size() && v.back() == 0)v.pop_back();
}
vector<ll> operator+(vector<ll>& a, vector<ll> b) {
	vector<ll> res(max(a.size(), b.size()));
	rep(i, a.size())res[i] += a[i];
	rep(i, b.size())res[i] += b[i];
	normalize(res);
	return res;
}
vector<ll> operator*(vector<ll>& a, vector<ll>& b) {
	if (min(a.size(), b.size()) <= 60) {
		vector<ll> res(a.size() + b.size() - 1);
		rep(i, a.size())rep(j, b.size()) {
			res[i + j] += a[i] * b[j];
		}
		normalize(res);
		return res;
	}
	poly ca(a.size()), cb(b.size());
	rep(i, a.size())ca[i] = { a[i],0 };
	rep(i, b.size())cb[i] = { b[i],0 };
	poly ab = multiply(ca, cb);
	vector<ll> res(ab.size());
	rep(i, ab.size()) {
		res[i] = round(ab[i].first);
	}
	normalize(res);
	return res;
}
Data operator*(Data a, Data b) {
	Data res;
	res.v0 = a.v0 + (b.v0 * a.v1);
	res.v1 = a.v1 * b.v1;
	return res;
}
void solve() {
	int n; cin >> n;
	vector<int> p(n);
	rep(i, n)cin >> p[i];
	vector<int> c(n);
	BIT<int> bt(n + 1);
	per(i, n) {
		c[i] = bt.sum(p[i]);
		bt.add(p[i], 1);
	}
	vector<Data> vd;
	for (int i = 1; i <= n; i++) {
		Data cur; cur.init({ c[n - i],i });
		vd.push_back(cur);
	}
	while (vd.size() > 1) {
		vector<Data> nvd;
		for (int i = 0; i + 1 < vd.size(); i += 2) {
			Data cur = vd[i] * vd[i + 1];
			nvd.push_back(cur);
		}
		if (vd.size() % 2)nvd.push_back(vd.back());
		swap(vd, nvd);
	}
	vector<ll> res = vd[0].v0;
	res.push_back(0);
	res[0]++; normalize(res);
	string ans;
	rep(i, res.size()) {
		int v = res[i];
		assert(v < mm);
		rep(j, 6) {
			int r = v % 10;
			ans.push_back('0' + r);
			v /= 10;
		}
	}
	while (ans.back() == '0')ans.pop_back();
	reverse(all(ans));
	cout << ans << "\n";
	
}



signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	//cout << fixed << setprecision(12);
	//init_f();
	//init();
	//while(true)
	//expr();
	//int t; cin >> t; rep(i, t)
	solve();
	return 0;
}
0