結果
問題 | No.2674 k-Walk on Bipartite |
ユーザー |
|
提出日時 | 2024-03-15 23:16:50 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 230 ms / 2,000 ms |
コード長 | 4,054 bytes |
コンパイル時間 | 2,026 ms |
コンパイル使用メモリ | 183,784 KB |
実行使用メモリ | 35,712 KB |
最終ジャッジ日時 | 2024-09-30 02:50:14 |
合計ジャッジ時間 | 5,385 ms |
ジャッジサーバーID (参考情報) |
judge2 / 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;using ll = long long;using pll = pair<ll, ll>;#define drep(i, cc, n) for (ll i = (cc); i <= (n); ++i)#define rep(i, n) drep(i, 0, n - 1)#define all(a) (a).begin(), (a).end()#define pb push_back#define fi first#define se secondmt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());const ll MOD1000000007 = 1000000007;const ll MOD998244353 = 998244353;const ll MOD[3] = {999727999, 1070777777, 1000000007};const ll LINF = 1LL << 60LL;const int IINF = (1 << 30) - 1;template<typename T>struct edge{int from, to;T cost;int id;edge(){}edge(int to, T cost=1) : from(-1), to(to), cost(cost){}edge(int to, T cost, int id) : from(-1), to(to), cost(cost), id(id){}edge(int from, int to, T cost, int id) : from(from), to(to), cost(cost), id(id){}};template<typename T>struct redge{int from, to;T cap, cost;int rev;redge(int to, T cap, T cost=(T)(1)) : from(-1), to(to), cap(cap), cost(cost){}redge(int to, T cap, T cost, int rev) : from(-1), to(to), cap(cap), cost(cost), rev(rev){}};template<typename T> using Edges = vector<edge<T>>;template<typename T> using weighted_graph = vector<Edges<T>>;template<typename T> using tree = vector<Edges<T>>;using unweighted_graph = vector<vector<int>>;template<typename T> using residual_graph = vector<vector<redge<T>>>;vector<long long> dijkstra(weighted_graph<long long> G, int src){int n = (int)G.size();vector<long long> dist(n, LINF);dist[src] = 0;priority_queue<pair<long long, int>, vector<pair<long long, int>>, greater<pair<long long, int>>> PQ;PQ.push({0, src});while(!PQ.empty()){int v = PQ.top().second;long long tmp = PQ.top().first;PQ.pop();if(dist[v] < tmp) continue;for(edge<long long> e : G[v]){if(dist[v]+e.cost < dist[e.to]){dist[e.to] = dist[v]+e.cost;PQ.push({dist[e.to], e.to});}}}return dist;}struct union_find{vector<int> par;vector<int> siz;union_find(int n) : par(n), siz(n, 1){for(int i=0; i<n; i++) par[i] = i;}int root(int x){if (par[x] == x) return x;return par[x] = root(par[x]);}void unite(int x, int y){int rx = root(x);int ry = root(y);if (rx == ry) return;if (siz[rx] < siz[ry]) swap(rx, ry);siz[rx] += siz[ry];par[ry] = rx;}bool same(int x, int y){int rx = root(x);int ry = root(y);return rx == ry;}int size(int x){return siz[root(x)];}};void solve(){int n, m; cin >> n >> m;int s, t, k; cin >> s >> t >> k;s--; t--;weighted_graph<ll> G(n);union_find uf(n);for(int i=0; i<m; i++){int u, v; cin >> u >> v;u--; v--;G[u].pb(edge<ll>(v));G[v].pb(edge<ll>(u));uf.unite(u, v);}if(s==t){if(k%2==1){cout << "No\n";}else{if(uf.size(s)>=2){cout << "Yes\n";}else{if(n==1){cout << "No\n";}else if(n>=2){cout << "Unknown\n";}}}return;}if(!uf.same(s, t)){if(n>=3){cout << "Unknown\n";}else if(n==2){if(k%2==1){cout << "Unknown\n";}else{cout << "No\n";}}else if(n==1){cout << "No\n";}return;}vector<ll> dist = dijkstra(G, s);if(dist[t]%2 != k%2){cout << "No\n";}else{if(dist[t]<=k){cout << "Yes\n";}else{cout << "Unknown\n";}}}int main(){cin.tie(nullptr);ios::sync_with_stdio(false);int T=1;//cin >> T;while(T--) solve();}