oj.uz

Submission #443000

# Submission time Handle Problem Language Result Execution time Memory
443000 2021-07-09T13:13:27 Z wind_reaper Olympic Bus (JOI20_ho_t4) C++17
100 / 100
 141 ms 3652 KB 
#include <bits/stdc++.h>
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
*/

using namespace std;
// using namespace __gnu_pbds;
using namespace chrono;

// mt19937 rng((int) std::chrono::steady_clock::now().time_since_epoch().count());
/*
template <class T> using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;
*/

//***************** CONSTANTS *****************

const int MXN = 200;
const int MXM = 50000;
const int64_t INF = 1'500'000'000'000'000;

//***************** GLOBAL VARIABLES *****************

vector<array<int, 2>> g[2][MXN];
int U[MXM], V[MXM], w[MXM], rev[MXM];
int N, M;

//***************** AUXILIARY STRUCTS *****************

void dijkstra(int S, int T, int idx, int64_t dist[], bool used[]){
	int prev[N]; memset(prev, -1, sizeof prev);

	vector<bool> vis(N, false);

	for(int i = 0; i <= N; i++) dist[i] = INF;
	dist[S] = 0;

	while(true){
		int u = N;
		for(int i = 0; i < N; i++)
			if(!vis[i] && dist[i] < dist[u])
				u = i;

		if(u == N)
			break;

		for(auto& [v, i] : g[idx][u])
			if(dist[v] > dist[u] + w[i])
				dist[v] = dist[u] + w[i], prev[v] = i;

		vis[u] = 1;
	}
	
	if(idx) return;

	for(int cur = T; prev[cur] != -1; cur = U[prev[cur]])
		used[prev[cur]] = 1;
}

int64_t dijkstra(int S, int T, int idx){
	vector<bool> vis(N, 0);
	int64_t dist[N + 1];
	for(int i = 0; i <= N; i++)
		dist[i] = INF;

	dist[S] = 0;

	while(true){
		int u = N;
		for(int i = 0; i < N; i++)
			if(!vis[i] && dist[i] < dist[u])
				u = i;

		if(u == N)
			break;

		for(auto& [v, i] : g[0][u])
			if(i != idx){
				dist[v] = min(dist[v], dist[u] + w[i]);
			}

		if(V[idx] == u)
			dist[U[idx]] = min(dist[U[idx]], dist[u] + w[idx]);

		vis[u] = 1;
	}

	return dist[T];
}

//***************** MAIN BODY *****************

void solve(){
	cin >> N >> M;

	for(int i = 0; i < M; i++){
		cin >> U[i] >> V[i] >> w[i] >> rev[i];
		--U[i], --V[i];
		g[0][U[i]].push_back({V[i], i});
		g[1][V[i]].push_back({U[i], i});
	}

	bool used[3][M];
	memset(used, 0, sizeof used);

	int64_t from[2][N + 1], to[2][N + 1];

	dijkstra(0, N - 1, 0, from[0], used[0]);
	dijkstra(N - 1, 0, 0, from[1], used[1]);
	dijkstra(0, N - 1, 1, to[0], used[2]);
	dijkstra(N - 1, 0, 1, to[1], used[2]);

	int64_t ans = from[0][N - 1] + from[1][0];

	for(int i = 0; i < M; i++){
		int64_t temp = rev[i];

		if(used[0][i]) 
			temp += dijkstra(0, N - 1, i);
		else temp += min(from[0][N - 1], from[0][V[i]] + to[1][U[i]] + w[i]);

		if(used[1][i])
			temp += dijkstra(N - 1, 0, i);
		else temp += min(from[1][0], from[1][V[i]] + to[0][U[i]] + w[i]);

		ans = min(ans, temp);
	}

	cout << (ans >= INF ? -1 : ans) << '\n';
}

//***************** *****************

int32_t main(){
	ios_base::sync_with_stdio(NULL);
	cin.tie(NULL);

	#ifdef LOCAL
		auto begin = high_resolution_clock::now();
	#endif

	int tc = 1;
	// cin >> tc; 
	for (int t = 0; t < tc; t++)
		solve();

	#ifdef LOCAL 
		auto end = high_resolution_clock::now();
		cout << fixed << setprecision(4);
		cout << "Execution Time: " << duration_cast<duration<double>>(end - begin).count() << "seconds" << endl;
	#endif

	return 0;
}

/*
If code gives a WA, check for the following : 
1. I/O format

2. Are you clearing all global variables in between tests if multitests are a thing

3. Can you definitively prove the logic
*/

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 416 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 3 ms 332 KB Output is correct
4 Correct 4 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 0 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 51 ms 380 KB Output is correct
11 Correct 49 ms 332 KB Output is correct
12 Correct 52 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 3 ms 332 KB Output is correct
15 Correct 2 ms 332 KB Output is correct
16 Correct 4 ms 400 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 27 ms 3524 KB Output is correct
2 Correct 35 ms 3464 KB Output is correct
3 Correct 28 ms 3576 KB Output is correct
4 Correct 4 ms 332 KB Output is correct
5 Correct 4 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 25 ms 3604 KB Output is correct
10 Correct 26 ms 3408 KB Output is correct
11 Correct 33 ms 3508 KB Output is correct
12 Correct 29 ms 3500 KB Output is correct
13 Correct 28 ms 3396 KB Output is correct
14 Correct 29 ms 3652 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 20 ms 1956 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 24 ms 3356 KB Output is correct
6 Correct 0 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 24 ms 3276 KB Output is correct
9 Correct 23 ms 3176 KB Output is correct
10 Correct 24 ms 3260 KB Output is correct
11 Correct 24 ms 3192 KB Output is correct
12 Correct 25 ms 3208 KB Output is correct
13 Correct 0 ms 332 KB Output is correct
14 Correct 0 ms 332 KB Output is correct
15 Correct 0 ms 332 KB Output is correct
16 Correct 0 ms 332 KB Output is correct
17 Correct 1 ms 332 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 24 ms 3248 KB Output is correct
20 Correct 33 ms 3212 KB Output is correct
21 Correct 25 ms 3184 KB Output is correct
22 Correct 24 ms 3148 KB Output is correct

Subtask #4
63.0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 416 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 3 ms 332 KB Output is correct
4 Correct 4 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 332 KB Output is correct
8 Correct 0 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 51 ms 380 KB Output is correct
11 Correct 49 ms 332 KB Output is correct
12 Correct 52 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 3 ms 332 KB Output is correct
15 Correct 2 ms 332 KB Output is correct
16 Correct 4 ms 400 KB Output is correct
17 Correct 27 ms 3524 KB Output is correct
18 Correct 35 ms 3464 KB Output is correct
19 Correct 28 ms 3576 KB Output is correct
20 Correct 4 ms 332 KB Output is correct
21 Correct 4 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 25 ms 3604 KB Output is correct
26 Correct 26 ms 3408 KB Output is correct
27 Correct 33 ms 3508 KB Output is correct
28 Correct 29 ms 3500 KB Output is correct
29 Correct 28 ms 3396 KB Output is correct
30 Correct 29 ms 3652 KB Output is correct
31 Correct 3 ms 332 KB Output is correct
32 Correct 1 ms 332 KB Output is correct
33 Correct 20 ms 1956 KB Output is correct
34 Correct 1 ms 332 KB Output is correct
35 Correct 24 ms 3356 KB Output is correct
36 Correct 0 ms 332 KB Output is correct
37 Correct 1 ms 332 KB Output is correct
38 Correct 24 ms 3276 KB Output is correct
39 Correct 23 ms 3176 KB Output is correct
40 Correct 24 ms 3260 KB Output is correct
41 Correct 24 ms 3192 KB Output is correct
42 Correct 25 ms 3208 KB Output is correct
43 Correct 0 ms 332 KB Output is correct
44 Correct 0 ms 332 KB Output is correct
45 Correct 0 ms 332 KB Output is correct
46 Correct 0 ms 332 KB Output is correct
47 Correct 1 ms 332 KB Output is correct
48 Correct 0 ms 332 KB Output is correct
49 Correct 24 ms 3248 KB Output is correct
50 Correct 33 ms 3212 KB Output is correct
51 Correct 25 ms 3184 KB Output is correct
52 Correct 24 ms 3148 KB Output is correct
53 Correct 29 ms 3288 KB Output is correct
54 Correct 29 ms 3308 KB Output is correct
55 Correct 29 ms 3292 KB Output is correct
56 Correct 3 ms 380 KB Output is correct
57 Correct 2 ms 392 KB Output is correct
58 Correct 124 ms 2508 KB Output is correct
59 Correct 125 ms 2584 KB Output is correct
60 Correct 127 ms 2596 KB Output is correct
61 Correct 120 ms 2508 KB Output is correct
62 Correct 126 ms 2520 KB Output is correct
63 Correct 126 ms 2604 KB Output is correct
64 Correct 141 ms 2684 KB Output is correct
65 Correct 120 ms 2784 KB Output is correct
66 Correct 108 ms 2760 KB Output is correct
67 Correct 18 ms 2444 KB Output is correct
68 Correct 28 ms 3468 KB Output is correct
69 Correct 26 ms 3420 KB Output is correct
70 Correct 29 ms 3504 KB Output is correct
71 Correct 30 ms 3424 KB Output is correct
72 Correct 27 ms 3508 KB Output is correct
73 Correct 29 ms 3508 KB Output is correct
74 Correct 30 ms 3524 KB Output is correct