Submission #774575

#	Time	Username	Problem	Language	Result	Execution time	Memory
774575		NK_	Traffic (CEOI11_tra)	C++17	100 / 100	522 ms	50868 KiB

tra

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>
 
using namespace std;
 
#define nl '\n'
#define f first
#define s second
#define mp make_pair
#define sz(x) int(x.size())
 
#define pb push_back
 
using pi = pair<int, int>;
template<class T> using V = vector<T>;
 
const int INF = 1e9 + 10;
 
int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	int N, M, A, B; cin >> N >> M >> A >> B;
 
	V<pi> P(N); for(auto& x : P) cin >> x.f >> x.s;
 
	V<V<int>> adj(N);
 
	for(int i = 0; i < M; i++) {
		int u, v, d; cin >> u >> v >> d; --u, --v, --d;
 
		adj[u].pb(v);
		if (d) adj[v].pb(u);
	}
 
	V<int> low(N, INF), disc(N, 0), comp(N, -1), st, comps;
 
  	// FIND SCCs
	int t = 0;
	function<int(int)> dfs = [&](int u) {
		st.pb(u);
		low[u] = disc[u] = ++t;
 
		for(const auto &v : adj[u]) {
			if (comp[v] == -1) low[u] = min(low[u], disc[v] ?: dfs(v));
		}
 
		if (low[u] == disc[u]) {
			comps.pb(u);
			for(int v = -1; v != u; ) comp[v = st.back()] = u, st.pop_back();
		}	
 
		return low[u];
	};
 
	for(int i = 0; i < N; i++) if (!disc[i]) dfs(i);
 
 
 	// SCCs
	V<V<int>> C(N); 
	for(int i = 0; i < N; i++) {
		C[comp[i]].pb(i);
	}
  
  
 	// WEST JUNCTIONS
	V<int> found(N);
	function<void(int)> see = [&](int u) {
		found[u] = 1;
		for(const auto &v : adj[u]) if (!found[v]) see(v);
	};
	
	V<int> W;
	for(int i = 0; i < N; i++) {
		if (P[i].f == 0) {
			W.pb(i); see(i);
		}
	}
 
	sort(begin(W), end(W), [&](int x, int y) {
		return P[x].s > P[y].s;
	});
 
 
 	// EAST JUNCTIONS
	V<int> E;
	for(int i = 0; i < N; i++) if (found[i]) {
		if (P[i].f == A) E.pb(i);
	}
 
	sort(begin(E), end(E), [&](int x, int y) {
		return P[x].s > P[y].s;
	});
 
 
 	// FIND INTERVALS OF JUNCTIONS
	V<int> L(N, INF), R(N, -INF);
	for(int i = 0; i < sz(E); i++) {
		int e = E[i];
		L[comp[e]] = min(L[comp[e]], i);
		R[comp[e]] = max(R[comp[e]], i);
	}
 
	for(const auto &c : comps) {
		for(const auto &u : C[c]) for(const auto &v : adj[u]) {
			int cv = comp[v];
			L[c] = min(L[c], L[cv]);
			R[c] = max(R[c], R[cv]);
		}
	}
	
	for(auto u : W) cout << max(0, R[comp[u]] - L[comp[u]] + 1) << nl;
 
    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 8 / 8
• Subtask 4: 8 / 8
• Subtask 5: 8 / 8
• Subtask 6: 8 / 8
• Subtask 7: 8 / 8
• Subtask 8: 8 / 8
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 9 / 9
• Subtask 12: 9 / 9