結果
| 問題 | No.2089 置換の符号 |
| ユーザー |
 tokusakurai
|
| 提出日時 | 2022-09-30 22:29:44 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 4 ms / 2,000 ms |
| コード長 | 5,905 bytes |
| コンパイル時間 | 2,248 ms |
| コンパイル使用メモリ | 202,408 KB |
| 最終ジャッジ日時 | 2025-02-07 19:39:03 |
|
ジャッジサーバーID （参考情報） |
judge4 / judge2 |
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| ファイルパターン | 結果 |
|---|---|
| other | AC * 33 |
ソースコード
#include <bits/stdc++.h>using namespace std;#define rep(i, n) for (int i = 0; i < (n); i++)#define per(i, n) for (int i = (n)-1; i >= 0; i--)#define rep2(i, l, r) for (int i = (l); i < (r); i++)#define per2(i, l, r) for (int i = (r)-1; i >= (l); i--)#define each(e, v) for (auto &e : v)#define MM << " " <<#define pb push_back#define eb emplace_back#define all(x) begin(x), end(x)#define rall(x) rbegin(x), rend(x)#define sz(x) (int)x.size()using ll = long long;using pii = pair<int, int>;using pil = pair<int, ll>;using pli = pair<ll, int>;using pll = pair<ll, ll>;template <typename T>using minheap = priority_queue<T, vector<T>, greater<T>>;template <typename T>using maxheap = priority_queue<T>;template <typename T>bool chmax(T &x, const T &y) {return (x < y) ? (x = y, true) : false;}template <typename T>bool chmin(T &x, const T &y) {return (x > y) ? (x = y, true) : false;}template <typename T>int flg(T x, int i) {return (x >> i) & 1;}template <typename T>void print(const vector<T> &v, T x = 0) {int n = v.size();for (int i = 0; i < n; i++) cout << v[i] + x << (i == n - 1 ? '\n' : ' ');if (v.empty()) cout << '\n';}template <typename T>void printn(const vector<T> &v, T x = 0) {int n = v.size();for (int i = 0; i < n; i++) cout << v[i] + x << '\n';}template <typename T>int lb(const vector<T> &v, T x) {return lower_bound(begin(v), end(v), x) - begin(v);}template <typename T>int ub(const vector<T> &v, T x) {return upper_bound(begin(v), end(v), x) - begin(v);}template <typename T>void rearrange(vector<T> &v) {sort(begin(v), end(v));v.erase(unique(begin(v), end(v)), end(v));}template <typename T>vector<int> id_sort(const vector<T> &v, bool greater = false) {int n = v.size();vector<int> ret(n);iota(begin(ret), end(ret), 0);sort(begin(ret), end(ret), [&](int i, int j) { return greater ? v[i] > v[j] : v[i] < v[j]; });return ret;}template <typename S, typename T>pair<S, T> operator+(const pair<S, T> &p, const pair<S, T> &q) {return make_pair(p.first + q.first, p.second + q.second);}template <typename S, typename T>pair<S, T> operator-(const pair<S, T> &p, const pair<S, T> &q) {return make_pair(p.first - q.first, p.second - q.second);}template <typename S, typename T>istream &operator>>(istream &is, pair<S, T> &p) {S a;T b;is >> a >> b;p = make_pair(a, b);return is;}template <typename S, typename T>ostream &operator<<(ostream &os, const pair<S, T> &p) {return os << p.first << ' ' << p.second;}struct io_setup {io_setup() {ios_base::sync_with_stdio(false);cin.tie(NULL);cout << fixed << setprecision(15);}} io_setup;const int inf = (1 << 30) - 1;const ll INF = (1LL << 60) - 1;// const int MOD = 1000000007;const int MOD = 998244353;template <typename T>struct Binary_Indexed_Tree {vector<T> bit;const int n;Binary_Indexed_Tree(const vector<T> &v) : n((int)v.size()) {bit.resize(n + 1);copy(begin(v), end(v), begin(bit) + 1);for (int a = 2; a <= n; a <<= 1) {for (int b = a; b <= n; b += a) bit[b] += bit[b - a / 2];}}Binary_Indexed_Tree(int n, const T &x) : Binary_Indexed_Tree(vector<T>(n, x)) {}void add(int i, const T &x) {for (i++; i <= n; i += (i & -i)) bit[i] += x;}void change(int i, const T &x) { add(i, x - query(i, i + 1)); }T sum(int i) const {i = min(i, n);T ret = 0;for (; i > 0; i -= (i & -i)) ret += bit[i];return ret;}T query(int l, int r) const {if (l >= r) return 0;return sum(r) - sum(l);}T operator[](int i) const { return query(i, i + 1); }// v[0]+...+v[r] >= x を満たす最小の r (なければ n)int lower_bound(T x) const {int ret = 0;for (int k = 31 - __builtin_clz(n); k >= 0; k--) {if (ret + (1 << k) <= n && bit[ret + (1 << k)] < x) x -= bit[ret += (1 << k)];}return ret;}// v[0]+...+v[r] > x を満たす最小の r (なければ n)int upper_bound(T x) const {int ret = 0;for (int k = 31 - __builtin_clz(n); k >= 0; k--) {if (ret + (1 << k) <= n && bit[ret + (1 << k)] <= x) x -= bit[ret += (1 << k)];}return ret;}};template <typename T>long long inversion_number(const vector<T> &a) {int n = a.size();vector<int> v(n);iota(begin(v), end(v), 0);sort(begin(v), end(v), [&](int i, int j) {if (a[i] != a[j]) return a[i] < a[j];return i < j;});Binary_Indexed_Tree<int> bit(n, 0);long long ret = 0;for (int i = 0; i < n; i++) {ret += bit.query(v[i] + 1, n);bit.add(v[i], 1);}return ret;}// a を b に変換するのに必要な最小バブルソート回数template <typename T>long long inversion_number(const vector<T> &a, const vector<T> &b) {int n = a.size();assert(b.size() == n);vector<int> u(n), v(n);iota(begin(u), end(u), 0);sort(begin(u), end(u), [&](int i, int j) {if (a[i] != a[j]) return a[i] < a[j];return i < j;});iota(begin(v), end(v), 0);sort(begin(v), end(v), [&](int i, int j) {if (b[i] != b[j]) return b[i] < b[j];return i < j;});vector<int> w(n);for (int i = 0; i < n; i++) {if (a[u[i]] != b[v[i]]) return -1;w[v[i]] = u[i];}Binary_Indexed_Tree<int> bit(n, 0);long long ret = 0;for (int i = 0; i < n; i++) {ret += bit.query(w[i] + 1, n);bit.add(w[i], 1);}return ret;}int main() {int N;cin >> N;vector<int> v(N);rep(i, N) cin >> v[i];cout << (inversion_number(v) & 1 ? -1 : 1) << '\n';}