結果
問題 | No.1244 Black Segment |
ユーザー |
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提出日時 | 2020-10-02 23:11:27 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 170 ms / 2,000 ms |
コード長 | 4,764 bytes |
コンパイル時間 | 2,137 ms |
コンパイル使用メモリ | 205,560 KB |
最終ジャッジ日時 | 2025-01-15 01:13:26 |
ジャッジサーバーID (参考情報) |
judge5 / judge3 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 36 |
ソースコード
#include <bits/stdc++.h>using namespace std;#define int long long#define rep(i, n) for (int i = 0; i < (int) (n); i++)#define reps(i, n) for (int i = 1; i <= (int) (n); i++)#define all(a) (a).begin(), (a).end()#define uniq(a) (a).erase(unique(all(a)), (a).end())#define bit(n) (1LL << (n))#define dump(a) cerr << #a " = " << (a) << endlusing vint = vector<int>;using pint = pair<int, int>;using vpint = vector<pint>;template<typename T> using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;constexpr double PI = 3.1415926535897932384626433832795028;constexpr int DY[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0};constexpr int DX[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0};int sign(int a) { return (a > 0) - (a < 0); }int gcd(int a, int b) {while (b) { swap(a %= b, b); }return a;}int lcm(int a, int b) { return a / gcd(a, b) * b; }int cdiv(int a, int b) { return (a - 1 + b) / b; }template<typename T> void fin(T a) {cout << a << endl;exit(0);}template<typename T> T sq(T a) { return a * a; }template<typename T, typename U> bool chmax(T &a, const U &b) {if (a < b) {a = b;return true;}return false;}template<typename T, typename U> bool chmin(T &a, const U &b) {if (b < a) {a = b;return true;}return false;}template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &a) {os << "(" << a.first << ", " << a.second << ")";return os;}template<typename T> ostream &operator<<(ostream &os, const vector<T> &a) {os << "{";for (auto itr = a.begin(); itr != a.end(); itr++) {os << *itr << (next(itr) != a.end() ? ", " : "");}os << "}";return os;}template<typename T> ostream &operator<<(ostream &os, const deque<T> &a) {os << "{";for (auto itr = a.begin(); itr != a.end(); itr++) {os << *itr << (next(itr) != a.end() ? ", " : "");}os << "}";return os;}template<typename T> ostream &operator<<(ostream &os, const set<T> &a) {os << "{";for (auto itr = a.begin(); itr != a.end(); itr++) {os << *itr << (next(itr) != a.end() ? ", " : "");}os << "}";return os;}template<typename T> ostream &operator<<(ostream &os, const multiset<T> &a) {os << "{";for (auto itr = a.begin(); itr != a.end(); itr++) {os << *itr << (next(itr) != a.end() ? ", " : "");}os << "}";return os;}template<typename T, typename U> ostream &operator<<(ostream &os, const map<T, U> &a) {os << "{";for (auto itr = a.begin(); itr != a.end(); itr++) {os << *itr << (next(itr) != a.end() ? ", " : "");}os << "}";return os;}struct setup {static constexpr int PREC = 20;setup() {cout << fixed << setprecision(PREC);cerr << fixed << setprecision(PREC);};} setup;template<typename S>struct dijkstra {using T = typename S::T;using E = typename S::E;std::vector<std::vector<int>> adj;std::vector<std::vector<E>> cost;dijkstra(int n) : adj(n), cost(n) {}void add_edge(int from, int to, E cost) { adj[from].emplace_back(to), this->cost[from].emplace_back(cost); }std::vector<T> get_dist(int s) {std::vector<T> ret(adj.size(), S::inf());using P = std::pair<T, int>;auto c = [&](P a, P b) -> bool { return S::less(b.first, a.first); };std::priority_queue<P, std::vector<P>, decltype(c)> pq(c);ret[s] = S::zero();pq.emplace(ret[s], s);while (!pq.empty()) {P p = pq.top();pq.pop();int v = p.second;if (S::less(ret[v], p.first)) { continue; }for (int i = 0; i < adj[v].size(); i++) {int u = adj[v][i];T dist = S::plus(ret[v], cost[v][i]);if (S::less(dist, ret[u])) { ret[u] = dist, pq.emplace(ret[u], u); }}}return ret;}};struct int_dij {using T = int;using E = int;static T zero() { return 0; }static T inf() { return std::numeric_limits<T>::max(); }static T plus(const T &a, const E &b) { return a == inf() ? inf() : a + b; }static bool less(const T &a, const T &b) { return a < b; }};signed main() {int N, M, A, B;cin >> N >> M >> A >> B;dijkstra<int_dij> dij(N + 3);int s = N + 1, t = N + 2;rep(i, A) { dij.add_edge(s, i, 0); }for (int i = B; i <= N; i++) { dij.add_edge(i, t, 0); }rep(i, M) {int L, R;cin >> L >> R, L--;dij.add_edge(L, R, 1);dij.add_edge(R, L, 1);}int ans = dij.get_dist(s)[t];if (ans == int_dij::inf()) { cout << -1 << endl; }else { cout << ans << endl; }}