oj.uz

Submission #246302

# Submission time Handle Problem Language Result Execution time Memory
246302 2020-07-08T15:27:54 Z LucaDantas Commuter Pass (JOI18_commuter_pass) C++17
100 / 100
 506 ms 31272 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;

#ifdef MY_DEBUG_FLAG
template<typename T> void debug(T a) { cerr << a << ' '; }
template<typename T, typename U> void debug(pair<T, U> a) { cerr << a.first << ' ' << a.second << ' '; }
template<typename T> void debug(vector<T> a) { for(auto it : a) debug(it);}
template<typename T> void debug(set<T> a) { for(auto it : a) debug(it);}
#define db(a) cerr << "DEBUG ( " << #a << " == "; debug(a); cerr << ")\n"
#else
#define db(...)
#endif

#define pb push_back
#define eb emplace_back
#define ff first
#define ss second
#define fast ios_base::sync_with_stdio(false), cout.tie(nullptr), cin.tie(nullptr)
#define sz(a) ((int)(a).size())
#define rep(i,a,b) for(int i=(a); i<(b); i++)
#define dec(i,n,a) for(int i=(n); i>=(a); i--)
#define clr(a,v) memset(a, v, sizeof(a))
#define all(a) (a).begin(),(a).end()

constexpr ll inf = 0x3f3f3f3f3f3f3f3f;
constexpr int MAXN = 1e5 + 10;
constexpr int mod = 1000000007;

struct Edge
{
	int u, v, w;
} edges[2*MAXN];

vector<pii> g[MAXN];

ll dist[MAXN][4]; // 0 -> s, 1 -> t, 2 -> u, 3 -> v

void dijkstra(int s, int k) {
	rep(i,0,MAXN) dist[i][k] = inf;
	
	priority_queue<pair<ll,int>, vector<pair<ll,int>>, greater<pair<ll,int>>> q;
	
	q.push({0ll, s});
	dist[s][k] = 0;
	
	bool mark[MAXN]; clr(mark, 0);

	while(!q.empty()) {
		int u = q.top().ss;
		q.pop();

		if(mark[u]) continue;
		mark[u] = 1;

		for(auto nxt : g[u]) {
			int v = nxt.ff, w = nxt.ss;
			if(dist[v][k] > dist[u][k] + 1ll*w) {
				dist[v][k] = dist[u][k] + 1ll*w;
				q.push({dist[v][k], v});
			}
		}
	}
}

vi dag[MAXN], inv_dag[MAXN], ord;

bool mark[MAXN];

void dfs(int u) {
	mark[u] = 1;
	for(auto v : dag[u])
		if(!mark[v])
			dfs(v);
	ord.pb(u);
}

int main() {
	int n, m, S, T, U, V; scanf("%d %d %d %d %d %d", &n, &m, &S, &T, &U, &V);
	rep(i,0,m) {
		int a, b, w; scanf("%d %d %d", &a, &b, &w);
		edges[i] = {a,b,w};
		g[a].pb({b,w});
		g[b].pb({a,w});
	}

	dijkstra(S,0);
	dijkstra(T,1);
	dijkstra(U,2);
	dijkstra(V,3);

	ll menor = dist[T][0];

	rep(i,0,m) {
		int u = edges[i].u, v = edges[i].v, w = edges[i].w;
		if(dist[u][0] + 1ll*w + dist[v][1] == menor)
			dag[u].pb(v), inv_dag[v].pb(u);
		if(dist[v][0] + 1ll*w + dist[u][1] == menor)
			dag[v].pb(u), inv_dag[u].pb(v);
	}

	dfs(S);

	reverse(all(ord));

	vector<ll> d(n+1);
 
	rep(i,1,n+1) d[i] = dist[i][2];
 
	for(auto x : ord) {
		for(auto y : dag[x]) {
			dist[y][2] = min(dist[x][2], dist[y][2]);
		}
	}

	reverse(all(ord));
 
	for(auto x : ord) {
		for(auto y : inv_dag[x]) {
			d[y] = min(d[x], d[y]);
		}
	}
 
	ll ans = inf;
 
	rep(i,1,n+1) {
		ans = min(ans, min(dist[i][2],d[i]) + dist[i][3]);
	}
 
	printf("%lld\n", ans);
}

Compilation message

commuter_pass.cpp: In function 'int main()':
commuter_pass.cpp:81:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n, m, S, T, U, V; scanf("%d %d %d %d %d %d", &n, &m, &S, &T, &U, &V);
                        ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
commuter_pass.cpp:83:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int a, b, w; scanf("%d %d %d", &a, &b, &w);
                ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 406 ms 26420 KB Output is correct
2 Correct 411 ms 25260 KB Output is correct
3 Correct 438 ms 31272 KB Output is correct
4 Correct 373 ms 26100 KB Output is correct
5 Correct 413 ms 26636 KB Output is correct
6 Correct 399 ms 26276 KB Output is correct
7 Correct 475 ms 27516 KB Output is correct
8 Correct 451 ms 26864 KB Output is correct
9 Correct 404 ms 25448 KB Output is correct
10 Correct 398 ms 25448 KB Output is correct
11 Correct 258 ms 22648 KB Output is correct
12 Correct 417 ms 25504 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 454 ms 26408 KB Output is correct
2 Correct 475 ms 26744 KB Output is correct
3 Correct 420 ms 25980 KB Output is correct
4 Correct 464 ms 26508 KB Output is correct
5 Correct 435 ms 27528 KB Output is correct
6 Correct 433 ms 30372 KB Output is correct
7 Correct 463 ms 30992 KB Output is correct
8 Correct 466 ms 26596 KB Output is correct
9 Correct 421 ms 27376 KB Output is correct
10 Correct 437 ms 26404 KB Output is correct
11 Correct 241 ms 25064 KB Output is correct
12 Correct 460 ms 30972 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 30 ms 12024 KB Output is correct
2 Correct 11 ms 10656 KB Output is correct
3 Correct 11 ms 10676 KB Output is correct
4 Correct 31 ms 13176 KB Output is correct
5 Correct 21 ms 11904 KB Output is correct
6 Correct 12 ms 10624 KB Output is correct
7 Correct 12 ms 10752 KB Output is correct
8 Correct 13 ms 10880 KB Output is correct
9 Correct 11 ms 10752 KB Output is correct
10 Correct 21 ms 11904 KB Output is correct
11 Correct 10 ms 10624 KB Output is correct
12 Correct 11 ms 10624 KB Output is correct
13 Correct 11 ms 10624 KB Output is correct
14 Correct 11 ms 10752 KB Output is correct
15 Correct 11 ms 10752 KB Output is correct

Subtask #4
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 406 ms 26420 KB Output is correct
2 Correct 411 ms 25260 KB Output is correct
3 Correct 438 ms 31272 KB Output is correct
4 Correct 373 ms 26100 KB Output is correct
5 Correct 413 ms 26636 KB Output is correct
6 Correct 399 ms 26276 KB Output is correct
7 Correct 475 ms 27516 KB Output is correct
8 Correct 451 ms 26864 KB Output is correct
9 Correct 404 ms 25448 KB Output is correct
10 Correct 398 ms 25448 KB Output is correct
11 Correct 258 ms 22648 KB Output is correct
12 Correct 417 ms 25504 KB Output is correct
13 Correct 454 ms 26408 KB Output is correct
14 Correct 475 ms 26744 KB Output is correct
15 Correct 420 ms 25980 KB Output is correct
16 Correct 464 ms 26508 KB Output is correct
17 Correct 435 ms 27528 KB Output is correct
18 Correct 433 ms 30372 KB Output is correct
19 Correct 463 ms 30992 KB Output is correct
20 Correct 466 ms 26596 KB Output is correct
21 Correct 421 ms 27376 KB Output is correct
22 Correct 437 ms 26404 KB Output is correct
23 Correct 241 ms 25064 KB Output is correct
24 Correct 460 ms 30972 KB Output is correct
25 Correct 30 ms 12024 KB Output is correct
26 Correct 11 ms 10656 KB Output is correct
27 Correct 11 ms 10676 KB Output is correct
28 Correct 31 ms 13176 KB Output is correct
29 Correct 21 ms 11904 KB Output is correct
30 Correct 12 ms 10624 KB Output is correct
31 Correct 12 ms 10752 KB Output is correct
32 Correct 13 ms 10880 KB Output is correct
33 Correct 11 ms 10752 KB Output is correct
34 Correct 21 ms 11904 KB Output is correct
35 Correct 10 ms 10624 KB Output is correct
36 Correct 11 ms 10624 KB Output is correct
37 Correct 11 ms 10624 KB Output is correct
38 Correct 11 ms 10752 KB Output is correct
39 Correct 11 ms 10752 KB Output is correct
40 Correct 377 ms 26800 KB Output is correct
41 Correct 429 ms 25300 KB Output is correct
42 Correct 462 ms 25372 KB Output is correct
43 Correct 231 ms 26992 KB Output is correct
44 Correct 237 ms 26964 KB Output is correct
45 Correct 491 ms 30244 KB Output is correct
46 Correct 460 ms 30112 KB Output is correct
47 Correct 389 ms 26112 KB Output is correct
48 Correct 256 ms 24816 KB Output is correct
49 Correct 383 ms 26184 KB Output is correct
50 Correct 460 ms 28988 KB Output is correct
51 Correct 506 ms 30416 KB Output is correct