結果
問題 | No.1244 Black Segment |
ユーザー |
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提出日時 | 2020-10-03 01:17:10 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 82 ms / 2,000 ms |
コード長 | 4,086 bytes |
コンパイル時間 | 2,141 ms |
コンパイル使用メモリ | 207,816 KB |
最終ジャッジ日時 | 2025-01-15 01:32:25 |
ジャッジサーバーID (参考情報) |
judge5 / judge4 |
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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 REP(i,n) for(ll i=0;i<(ll)n;i++)#define dump(x) cerr << "Line " << __LINE__ << ": " << #x << " = " << (x) << "\n";#define spa << " " <<#define fi first#define se second#define ALL(a) (a).begin(),(a).end()#define ALLR(a) (a).rbegin(),(a).rend()using ld = long double;using ll = long long;using ull = unsigned long long;using pii = pair<int, int>;using pll = pair<ll, ll>;using pdd = pair<ld, ld>;template<typename T> using V = vector<T>;template<typename T> using P = pair<T, T>;template<typename T> vector<T> make_vec(size_t n, T a) { return vector<T>(n, a); }template<typename... Ts> auto make_vec(size_t n, Ts... ts) { return vector<decltype(make_vec(ts...))>(n, make_vec(ts...)); }template<class S, class T> ostream& operator << (ostream& os, const pair<S, T> v){os << "(" << v.first << ", " << v.second << ")"; return os;}template<typename T> ostream& operator<<(ostream &os, const vector<T> &v) { for (auto &e : v) os << e << ' '; return os; }template<class T> ostream& operator<<(ostream& os, const vector<vector<T>> &v){ for(auto &e : v){os << e << "\n";} return os;}struct fast_ios { fast_ios(){ cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;template <class T> void UNIQUE(vector<T> &x) {sort(ALL(x));x.erase(unique(ALL(x)), x.end());}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; }void fail() { cout << -1 << '\n'; exit(0); }inline int popcount(const int x) { return __builtin_popcount(x); }inline int popcount(const ll x) { return __builtin_popcountll(x); }template<typename T> void debug(vector<vector<T>>&v,ll h,ll w){for(ll i=0;i<h;i++){cerr<<v[i][0];for(ll j=1;j<w;j++)cerr spa v[i][j];cerr<<"\n";}};template<typename T> void debug(vector<T>&v,ll n){if(n!=0)cerr<<v[0];for(ll i=1;i<n;i++)cerr spa v[i];cerr<<"\n";};const ll INF = (1ll<<62);// const ld EPS = 1e-10;// const ld PI = acos(-1.0);const ll mod = (int)1e9 + 7;//const ll mod = 998244353;template< typename T >struct edge {int src, to;T cost;edge(int to, T cost) : src(-1), to(to), cost(cost) {}edge(int src, int to, T cost) : src(src), to(to), cost(cost) {}edge &operator=(const int &x) {to = x;return *this;}operator int() const { return to; }};template< typename T >using Edges = vector< edge< T > >;template< typename T >using WeightedGraph = vector< Edges< T > >;using UnWeightedGraph = vector< vector< int > >;template< typename T >using Matrix = vector< vector< T > >;template< typename T >vector< T > Dijkstra(WeightedGraph< T > &g, int s) {const auto INF = numeric_limits< T >::max();vector< T > dist(g.size(), INF);using Pi = pair< T, int >;priority_queue< Pi, vector< Pi >, greater< Pi > > que;dist[s] = 0;que.emplace(dist[s], s);while(!que.empty()) {T cost;int idx;tie(cost, idx) = que.top();que.pop();if(dist[idx] < cost) continue;for(auto &e : g[idx]) {auto next_cost = cost + e.cost;if(dist[e.to] <= next_cost) continue;dist[e.to] = next_cost;que.emplace(dist[e.to], e.to);}}return dist;}int main(){ll N, M, A, B;cin >> N >> M >> A >> B;A--, B--;V<ll> L(M), R(M);REP(i, M) cin >> L[i] >> R[i];REP(i, M) L[i]--, R[i]--;using Graph = V<V<edge<ll>>>;Graph G(N+1);REP(i, M){G[L[i]].emplace_back(R[i]+1, 1);G[R[i]+1].emplace_back(L[i], 1);}REP(i, N+1){if(i<A){G[A].emplace_back(i, 0);G[i].emplace_back(A, 0);}if(B+1<i){G[B+1].emplace_back(i, 0);G[i].emplace_back(B+1, 0);}}// REP(i, N+1){// dump(i)// for(auto &e: G[i]) cout << e.to spa e.cost << endl;// }auto dist = Dijkstra(G, A);ll res = dist[B+1];cout << (res >= INF ? -1 : res) << endl;return 0;}