oj.uz

Submission #156507

# Submission time Handle Problem Language Result Execution time Memory
156507 2019-10-06T09:14:39 Z staniewzki Commuter Pass (JOI18_commuter_pass) C++14
100 / 100
 522 ms 22888 KB 
#include<bits/stdc++.h>
using namespace std;

ostream& operator<<(ostream &out, string str) {
	for(char c : str) out << c;
	return out;
}
 
template<class L, class R> ostream& operator<<(ostream &out, pair<L, R> p) {
	return out << "(" << p.first << ", " << p.second << ")";
}
 
template<class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
	out << "{";
	for(auto it = a.begin(); it != a.end(); it = next(it))
		out << (it != a.begin() ? ", " : "") << *it;
	return out << "}";
}
 
void dump() { cerr << "\n"; }
template<class T, class... Ts> void dump(T a, Ts... x) {
	cerr << a << ", ";
	dump(x...);
}
 
#ifdef DEBUG
#  define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#  define debug(...) false
#endif
 
#define REP(i, n) for(int i = 0; i < n; i++)
#define FOR(i, a, b) for(int i = a; i <= b; i++)
#define ST first
#define ND second
 
template<class T> int size(T && a) { return a.size(); }

using LL = long long;
using PII = pair<int, int>;

vector<vector<PII>> graph;
vector<LL> get_dist(int n, int s) {
	vector<LL> dist(n, 1e18);
	priority_queue<pair<LL, int>> Q;
	auto push = [&](int v, LL d) { 
		dist[v] = d;
		Q.emplace(-dist[v], v);
	};
	push(s, 0);

	while(!Q.empty()) {
		int v = Q.top().ND;
		Q.pop();
		for(PII e : graph[v]) {
			if(dist[e.ST] > dist[v] + e.ND)
				push(e.ST, dist[v] + e.ND);
		}
	}
	return dist;
}

vector<bool> vis;
vector<vector<int>> directed;
void dfs(int v, vector<LL> &d) {
	vis[v] = true;
	for(PII e : graph[v]) {
		if(d[v] == d[e.ST] + e.ND) {
			directed[v].emplace_back(e.ST);
			if(not vis[e.ST])
				dfs(e.ST, d);
		}
	}
}

vector<int> get_topologic_order(int n) {
	vector<int> ret, deg(n), Q;
	REP(i, n) for(int u : directed[i]) deg[u]++;	
	REP(i, n) if(deg[i] == 0) Q.emplace_back(i);

	while(!Q.empty()) {
		int v = Q.back();
		Q.pop_back();
		ret.emplace_back(v);
		for(int u : directed[v]) {
			if(--deg[u]	== 0)
				Q.emplace_back(u);
		}
	}

	return ret;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	int n, m;
	cin >> n >> m;
	
	int s, t, u, v;
	cin >> s >> t >> u >> v;
	s--, t--, u--, v--;
	graph.resize(n);
	REP(i, m) {
		int a, b, c;
		cin >> a >> b >> c;
		graph[a - 1].emplace_back(b - 1, c);
		graph[b - 1].emplace_back(a - 1, c);
	}

	auto dist_u = get_dist(n, u);
	auto dist_v = get_dist(n, v);
	auto dist_s = get_dist(n, s);
	auto dist_t = get_dist(n, t);

	debug(dist_s, dist_t);
	directed.resize(n);
	vis.resize(n);
	dfs(s, dist_t);

	vector<int> ord = get_topologic_order(n);
	vector<LL> min_u(n, 1e18), min_v(n, 1e18);
	LL ans = 1e18;

	for(int i : ord) {
		min_u[i] = min(min_u[i], dist_u[i]);
		min_v[i] = min(min_v[i], dist_v[i]);
		ans = min(ans, dist_u[i] + min_v[i]);
		ans = min(ans, min_u[i] + dist_v[i]);
		for(int j : directed[i]) {
			min_u[j] = min(min_u[j], min_u[i]);
			min_v[j] = min(min_v[j], min_v[i]);
		}
	}

	cout << ans << "\n";
}

Compilation message

commuter_pass.cpp: In function 'int main()':
commuter_pass.cpp:117:23: warning: statement has no effect [-Wunused-value]
  debug(dist_s, dist_t);
                       ^

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 396 ms 16980 KB Output is correct
2 Correct 380 ms 17396 KB Output is correct
3 Correct 416 ms 22368 KB Output is correct
4 Correct 323 ms 17196 KB Output is correct
5 Correct 341 ms 17916 KB Output is correct
6 Correct 386 ms 17020 KB Output is correct
7 Correct 517 ms 18408 KB Output is correct
8 Correct 405 ms 18056 KB Output is correct
9 Correct 423 ms 17136 KB Output is correct
10 Correct 320 ms 17024 KB Output is correct
11 Correct 131 ms 17412 KB Output is correct
12 Correct 381 ms 16984 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 389 ms 18948 KB Output is correct
2 Correct 398 ms 19344 KB Output is correct
3 Correct 411 ms 18960 KB Output is correct
4 Correct 408 ms 19296 KB Output is correct
5 Correct 404 ms 19776 KB Output is correct
6 Correct 376 ms 21992 KB Output is correct
7 Correct 460 ms 22472 KB Output is correct
8 Correct 428 ms 19332 KB Output is correct
9 Correct 469 ms 19796 KB Output is correct
10 Correct 424 ms 18884 KB Output is correct
11 Correct 149 ms 19280 KB Output is correct
12 Correct 399 ms 22316 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 892 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 19 ms 2424 KB Output is correct
5 Correct 11 ms 1400 KB Output is correct
6 Correct 3 ms 376 KB Output is correct
7 Correct 4 ms 504 KB Output is correct
8 Correct 4 ms 504 KB Output is correct
9 Correct 3 ms 376 KB Output is correct
10 Correct 11 ms 1400 KB Output is correct
11 Correct 3 ms 376 KB Output is correct
12 Correct 3 ms 376 KB Output is correct
13 Correct 2 ms 376 KB Output is correct
14 Correct 3 ms 376 KB Output is correct
15 Correct 3 ms 376 KB Output is correct

Subtask #4
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 396 ms 16980 KB Output is correct
2 Correct 380 ms 17396 KB Output is correct
3 Correct 416 ms 22368 KB Output is correct
4 Correct 323 ms 17196 KB Output is correct
5 Correct 341 ms 17916 KB Output is correct
6 Correct 386 ms 17020 KB Output is correct
7 Correct 517 ms 18408 KB Output is correct
8 Correct 405 ms 18056 KB Output is correct
9 Correct 423 ms 17136 KB Output is correct
10 Correct 320 ms 17024 KB Output is correct
11 Correct 131 ms 17412 KB Output is correct
12 Correct 381 ms 16984 KB Output is correct
13 Correct 389 ms 18948 KB Output is correct
14 Correct 398 ms 19344 KB Output is correct
15 Correct 411 ms 18960 KB Output is correct
16 Correct 408 ms 19296 KB Output is correct
17 Correct 404 ms 19776 KB Output is correct
18 Correct 376 ms 21992 KB Output is correct
19 Correct 460 ms 22472 KB Output is correct
20 Correct 428 ms 19332 KB Output is correct
21 Correct 469 ms 19796 KB Output is correct
22 Correct 424 ms 18884 KB Output is correct
23 Correct 149 ms 19280 KB Output is correct
24 Correct 399 ms 22316 KB Output is correct
25 Correct 11 ms 892 KB Output is correct
26 Correct 2 ms 376 KB Output is correct
27 Correct 2 ms 376 KB Output is correct
28 Correct 19 ms 2424 KB Output is correct
29 Correct 11 ms 1400 KB Output is correct
30 Correct 3 ms 376 KB Output is correct
31 Correct 4 ms 504 KB Output is correct
32 Correct 4 ms 504 KB Output is correct
33 Correct 3 ms 376 KB Output is correct
34 Correct 11 ms 1400 KB Output is correct
35 Correct 3 ms 376 KB Output is correct
36 Correct 3 ms 376 KB Output is correct
37 Correct 2 ms 376 KB Output is correct
38 Correct 3 ms 376 KB Output is correct
39 Correct 3 ms 376 KB Output is correct
40 Correct 323 ms 20680 KB Output is correct
41 Correct 351 ms 21184 KB Output is correct
42 Correct 327 ms 21280 KB Output is correct
43 Correct 148 ms 21864 KB Output is correct
44 Correct 253 ms 21948 KB Output is correct
45 Correct 522 ms 22712 KB Output is correct
46 Correct 370 ms 22676 KB Output is correct
47 Correct 358 ms 20664 KB Output is correct
48 Correct 182 ms 19188 KB Output is correct
49 Correct 289 ms 20260 KB Output is correct
50 Correct 368 ms 22140 KB Output is correct
51 Correct 386 ms 22888 KB Output is correct