結果
問題 | No.1244 Black Segment |
ユーザー |
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提出日時 | 2020-10-03 01:23:08 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 67 ms / 2,000 ms |
コード長 | 6,424 bytes |
コンパイル時間 | 1,620 ms |
コンパイル使用メモリ | 158,388 KB |
最終ジャッジ日時 | 2025-01-15 01:32:43 |
ジャッジサーバーID (参考情報) |
judge2 / judge1 |
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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 <limits>#include <initializer_list>#include <utility>#include <bitset>#include <tuple>#include <type_traits>#include <functional>#include <string>#include <array>#include <deque>#include <list>#include <queue>#include <stack>#include <vector>#include <map>#include <set>#include <unordered_map>#include <unordered_set>#include <iterator>#include <algorithm>#include <complex>#include <random>#include <numeric>#include <iostream>#include <iomanip>#include <sstream>#include <regex>#include <cassert>#include <cstddef>#include <variant>#define endl codeforces#define ALL(v) std::begin(v), std::end(v)#define ALLR(v) std::rbegin(v), std::rend(v)using ll = std::int64_t;using ull = std::uint64_t;using pii = std::pair<int, int>;using tii = std::tuple<int, int, int>;using pll = std::pair<ll, ll>;using tll = std::tuple<ll, ll, ll>;using size_type = ssize_t;template <typename T> using vec = std::vector<T>;template <typename T> using vvec = vec<vec<T>>;template <typename T> const T& var_min(const T &t) { return t; }template <typename T> const T& var_max(const T &t) { return t; }template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }template <typename T, std::size_t Head, std::size_t... Tail>struct multi_dim_array { using type = std::array<typename multi_dim_array<T, Tail...>::type, Head>; };template <typename T, std::size_t Head>struct multi_dim_array<T, Head> { using type = std::array<T, Head>; };template <typename T, std::size_t... Args> using mdarray = typename multi_dim_array<T, Args...>::type;template <typename T, typename F, typename... Args>void fill_seq(T &t, F f, Args... args) {if constexpr (std::is_invocable<F, Args...>::value) {t = f(args...);} else {for (size_type i = 0; i < t.size(); i++) fill_seq(t[i], f, args..., i);}}template <typename T> vec<T> make_v(size_type sz) { return vec<T>(sz); }template <typename T, typename... Tail>auto make_v(size_type hs, Tail&&... ts) {auto v = std::move(make_v<T>(std::forward<Tail>(ts)...));return vec<decltype(v)>(hs, v);}namespace init__ {struct InitIO {InitIO() {std::cin.tie(nullptr);std::ios_base::sync_with_stdio(false);std::cout << std::fixed << std::setprecision(30);}} init_io;}template <typename T>T ceil_pow2(T bound) {T ret = 1;while (ret < bound) ret *= 2;return ret;}template <typename T>T ceil_div(T a, T b) { return a / b + !!(a % b); }namespace graph {using Node = ll;using Weight = ll;using Edge = std::pair<Node, Weight>;template <bool Directed>struct Graph : public vvec<Edge> {using vvec<Edge>::vvec;void add_edge(Node f, Node t, Weight w = 1) {(*this)[f].emplace_back(t, w);if (!Directed) (*this)[t].emplace_back(f, w);}Graph<Directed> build_inv() const {Graph<Directed> ret(this->size());for (Node i = 0; i < this->size(); i++) {for (const Edge &e : (*this)[i]) {Node j;Weight w;std::tie(j, w) = e;if (!Directed && j < i) continue;ret.add_edge(j, i, w);}}return ret;}};template <typename Iterator>class dst_iterator {Iterator ite;public:dst_iterator(Iterator ite) : ite(ite) { }bool operator ==(const dst_iterator<Iterator> &oth) const {return ite == oth.ite;}bool operator !=(const dst_iterator<Iterator> &oth) const {return !(*this == oth);}bool operator <(const dst_iterator<Iterator> &oth) const {return ite < oth.ite;}bool operator >(const dst_iterator<Iterator> &oth) const {return ite > oth.ite;}bool operator <=(const dst_iterator<Iterator> &oth) const {return ite <= oth.ite;}bool operator >=(const dst_iterator<Iterator> &oth) const {return ite >= oth.ite;}const Node& operator *() {return ite->first;}const Node& operator *() const {return ite->first;}dst_iterator operator ++() {++ite;return ite;}};class dst_iteration {using ite_type = vec<Edge>::const_iterator;const vec<Edge> &edges;public:dst_iteration(const vec<Edge> &edges) : edges(edges) { }auto begin() const {return dst_iterator<ite_type>(edges.cbegin());}auto end() const {return dst_iterator<ite_type>(edges.cend());}};class dst_reverse_iteration {using ite_type = vec<Edge>::const_reverse_iterator;const vec<Edge> &edges;public:dst_reverse_iteration(const vec<Edge> &edges) : edges(edges) { }auto begin() const {return dst_iterator<ite_type>(edges.crbegin());}auto end() const {return dst_iterator<ite_type>(edges.crend());}};dst_iteration dst(const vec<Edge> &edges) {return dst_iteration(edges);}dst_reverse_iteration rdst(const vec<Edge> &edges) {return dst_reverse_iteration(edges);}}int main() {ll n, m, a, b;std::cin >> n >> m >> a >> b;a--;graph::Graph<false> g(n + 3);for (ll i = 0; i < m; i++) {ll c, d;std::cin >> c >> d;g.add_edge(c - 1, d);}ll start = n + 1, goal = n + 2;for (ll i = 0; i <= a; i++) g.add_edge(start, i);for (ll i = b; i <= n; i++) g.add_edge(i, goal);const ll inf = 5e15;vec<ll> dists(g.size(), inf);std::queue<ll> que;que.push(start);dists[start] = 0;while (que.size()) {ll cur = que.front();que.pop();ll d = dists[cur];ll nd = d + 1;for (ll nxt : graph::dst(g[cur])) {if (dists[nxt] <= nd) continue;dists[nxt] = nd;que.push(nxt);}}ll ans = dists[goal];if (ans == inf) ans = -1;else ans -= 2;std::cout << ans << "\n";return 0;}