結果
| 問題 |
No.2873 Kendall's Tau
|
| コンテスト | |
| ユーザー |
 fuppy_kyopro
|
| 提出日時 | 2024-09-06 21:48:07 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 7,915 bytes |
| コンパイル時間 | 2,804 ms |
| コンパイル使用メモリ | 227,564 KB |
| 最終ジャッジ日時 | 2025-02-24 04:13:21 |
|
ジャッジサーバーID （参考情報） |
judge3 / judge1 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 13 WA * 17 |
ソースコード
/*
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
//*/
// #include <atcoder/all>
// #include <atcoder/segtree>
#include <bits/stdc++.h>
using namespace std;
// using namespace atcoder;
// #define _GLIBCXX_DEBUG
#define DEBUG(x) cerr << #x << ": " << x << endl;
#define DEBUG_VEC(v) \
cerr << #v << ":"; \
for (int iiiiiiii = 0; iiiiiiii < v.size(); iiiiiiii++) \
cerr << " " << v[iiiiiiii]; \
cerr << endl;
#define DEBUG_MAT(v) \
cerr << #v << endl; \
for (int iv = 0; iv < v.size(); iv++) { \
for (int jv = 0; jv < v[iv].size(); jv++) { \
cerr << v[iv][jv] << " "; \
} \
cerr << endl; \
}
typedef long long ll;
// #define int ll
#define vi vector<int>
#define vl vector<ll>
#define vii vector<vector<int>>
#define vll vector<vector<ll>>
#define pii pair<int, int>
#define pis pair<int, string>
#define psi pair<string, int>
#define pll pair<ll, ll>
template <class S, class T>
pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) {
return pair<S, T>(s.first + t.first, s.second + t.second);
}
template <class S, class T>
pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template <class S, class T>
ostream &operator<<(ostream &os, pair<S, T> p) {
os << "(" << p.first << ", " << p.second << ")";
return os;
}
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep1(i, n) for (int i = 1; i <= (int)(n); i++)
#define rrep(i, n) for (int i = (int)(n) - 1; i >= 0; i--)
#define rrep1(i, n) for (int i = (int)(n); i > 0; i--)
#define REP(i, a, b) for (int i = a; i < b; i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(), c.end()
void YES(bool t = true) {
cout << (t ? "YES" : "NO") << endl;
}
void Yes(bool t = true) { cout << (t ? "Yes" : "No") << endl; }
void yes(bool t = true) { cout << (t ? "yes" : "no") << endl; }
void NO(bool t = true) { cout << (t ? "NO" : "YES") << endl; }
void No(bool t = true) { cout << (t ? "No" : "Yes") << endl; }
void no(bool t = true) { cout << (t ? "no" : "yes") << endl; }
template <class T>
bool chmax(T &a, const T &b) {
if (a < b) {
a = b;
return 1;
}
return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
if (a > b) {
a = b;
return 1;
}
return 0;
}
template <class T, class U>
T ceil_div(T a, U b) {
return (a + b - 1) / b;
}
template <class T>
T safe_mul(T a, T b) {
if (a == 0 || b == 0) return 0;
if (numeric_limits<T>::max() / a < b) return numeric_limits<T>::max();
return a * b;
}
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
int popcount(ll t) { return __builtin_popcountll(t); }
vector<int> gen_perm(int n) {
vector<int> ret(n);
iota(all(ret), 0);
return ret;
}
// int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
// int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
vi dx = {0, 0, -1, 1}, dy = {-1, 1, 0, 0};
vi dx2 = {1, 1, 0, -1, -1, -1, 0, 1}, dy2 = {0, 1, 1, 1, 0, -1, -1, -1};
struct Setup_io {
Setup_io() {
ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
cout << fixed << setprecision(25);
cerr << fixed << setprecision(25);
}
} setup_io;
// constexpr ll MOD = 1000000007;
constexpr ll MOD = 998244353;
// #define mp make_pair
template <typename T>
class Zaatsu {
bool is_build;
vector<T> elements;
public:
Zaatsu() : is_build(false) {}
void add(T x) {
elements.push_back(x);
}
void add(vector<T> x) {
for (int i = 0; i < (int)x.size(); i++) {
elements.push_back(x[i]);
}
}
int build() {
sort(elements.begin(), elements.end());
UNIQUE(elements);
is_build = true;
return elements.size();
}
int operator[](T x) {
assert(is_build);
return lower_bound(elements.begin(), elements.end(), x) - elements.begin();
}
T original(int i) {
assert(is_build);
return elements[i];
}
};
template <typename T>
class SegmentTree {
public:
using F = function<T(T &, T &)>;
int n;
vector<T> dat;
T e;
F query_func;
F update_func;
SegmentTree(vector<T> a, F query_func, F update_func, T e) : n(a.size()), query_func(query_func), update_func(update_func), e(e) {
if (n == 0) {
a.push_back(e);
n++;
}
dat.resize(4 * n);
init(0, 0, n, a);
}
void init(int k, int l, int r, vector<T> &a) {
if (r - l == 1) {
dat[k] = a[l];
} else {
int lch = 2 * k + 1, rch = 2 * k + 2;
init(lch, l, (l + r) / 2, a);
init(rch, (l + r) / 2, r, a);
dat[k] = query_func(dat[lch], dat[rch]);
}
}
void update(int k, T a, int v, int l, int r) {
if (r - l == 1) {
dat[v] = update_func(dat[v], a);
} else {
if (k < (l + r) / 2)
update(k, a, 2 * v + 1, l, (l + r) / 2);
else {
update(k, a, 2 * v + 2, (l + r) / 2, r);
}
dat[v] = query_func(dat[v * 2 + 1], dat[v * 2 + 2]);
}
}
void update(int k, T a) {
update(k, a, 0, 0, n);
}
T query(int a, int b, int k, int l, int r) {
if (r <= a || b <= l) {
return e;
}
if (a <= l && r <= b) {
return dat[k];
} else {
T ul = query(a, b, k * 2 + 1, l, (l + r) / 2);
T ur = query(a, b, k * 2 + 2, (l + r) / 2, r);
return query_func(ul, ur);
}
}
T query(int a, int b) {
return query(a, b, 0, 0, n);
}
int find(int a, int b, int k, int l, int r, int x) {
if (dat[k] < x || r <= a || b <= l) return -1;
if (l + 1 == r) {
if (dat[k] >= x)
return l;
else
return -1;
}
int rv = find(a, b, 2 * k + 2, (l + r) / 2, r, x);
if (rv != -1) return rv;
return find(a, b, 2 * k + 1, l, (l + r) / 2, x);
}
};
ll f(ll a, ll b) {
return a + b;
}
ll g(ll a, ll b) {
return a + b;
}
ll get_r(vl x, int cnt, ll n) {
vl num(cnt);
for (ll i : x) {
num[i]++;
}
ll ret = 0;
rep(i, cnt) {
ret += num[i] * (n - num[i]);
}
return ret / 2;
}
ll get_p(vector<pll> xy, int cnt, ll n) {
sort(all(xy));
vll x2y(cnt);
for (pll p : xy) {
x2y[p.first].push_back(p.second);
}
SegmentTree<ll> st(vl(cnt), f, g, 0);
ll ret = 0;
rep(x, cnt) {
for (ll y : x2y[x]) {
ret += st.query(0, y);
}
for (ll y : x2y[x]) {
st.update(y, 1);
}
}
return ret;
}
signed main() {
int n;
cin >> n;
vector<pll> xy(n);
Zaatsu<ll> za;
rep(i, n) {
cin >> xy[i].first >> xy[i].second;
za.add(xy[i].first);
za.add(xy[i].second);
}
int cnt = za.build();
rep(i, n) {
xy[i].first = za[xy[i].first];
xy[i].second = za[xy[i].second];
}
vl xs, ys;
rep(i, n) {
xs.push_back(xy[i].first);
ys.push_back(xy[i].second);
}
ll r = get_r(xs, cnt, n);
ll s = get_r(ys, cnt, n);
ll p = get_p(xy, cnt, n);
rep(i, n) {
xy[i].second = cnt - 1 - xy[i].second;
}
ll q = get_p(xy, cnt, n);
cout << (p - q) / sqrtl(r * s) << endl;
}