Submission #442485

# Submission time Handle Problem Language Result Execution time Memory
442485 2021-07-07T21:50:14 Z Aryan_Raina Olympic Bus (JOI20_ho_t4) C++17
100 / 100
134 ms 5656 KB
#include <bits/stdc++.h>
using namespace std;
 
#define int int64_t
#define ld long double
#define ar array
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
const int MOD = 1e9+7;
const int INF = 1e17+5;

const int MXN = 205, MXM = 50005;
vector<ar<int,2>> g[2][MXN];
int a[MXM], b[MXM], w[MXM], revw[MXM], N, M; 
void dijkstra(int s, int t, int typ, vector<int> &dist, vector<bool> &used) {
    vector<int> prev(N, -1); 
    used.resize(M, false); dist.resize(N+1, INF);
    vector<bool> vis(N, false);
    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[typ][u]) if (dist[v] > dist[u] + w[i])
            dist[v] = dist[u] + w[i], prev[v] = i;

        vis[u] = true;
    }

    if (typ) return;
    for (int cur = t; prev[cur] != -1; cur = a[prev[cur]])
        used[prev[cur]] = true;
}

int getdist(int s, int t, int reve) {
    vector<int> dist(N+1, INF);
    vector<bool> vis(N, false);
    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 != reve)
            dist[v] = min(dist[v], dist[u] + w[i]);

        if (b[reve] == u) 
            dist[a[reve]] = min(dist[a[reve]], dist[u] + w[reve]);

        vis[u] = true;
    }

    return dist[t];
}

void solve() {
    cin >> N >> M;
    for (int i = 0; i < M; i++) {
        cin >> a[i] >> b[i] >> w[i] >> revw[i];
        g[0][--a[i]].push_back({--b[i], i});
        g[1][b[i]].push_back({a[i], i});
    }

    vector<int> to1, toN, from1, fromN;
    vector<bool> used1, usedN, tmp;
    dijkstra(0, N-1, 0, from1, used1);
    dijkstra(N-1, 0, 0, fromN, usedN);
    dijkstra(0, N-1, 1, to1, tmp);
    dijkstra(N-1, 0, 1, toN, tmp);

    int ans = from1[N-1] + fromN[0];
    for (int i = 0; i < M; i++) {
        int lol = revw[i];

        if (used1[i]) lol += getdist(0, N-1, i);
        else lol += min(from1[N-1], from1[b[i]] + toN[a[i]] + w[i]);

        if (usedN[i]) lol += getdist(N-1, 0, i);
        else lol += min(fromN[0], fromN[b[i]] + to1[a[i]] + w[i]);

        ans = min(ans, lol);
    }

    if (ans >= INF/2) cout << -1 << '\n';
    else cout << ans << '\n';
}
 
int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0); 
 
    int t = 1; //cin >> t;
    while (t--) solve();   
}  
# Verdict Execution time Memory Grader output
1 Correct 4 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 3 ms 332 KB Output is correct
4 Correct 3 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 0 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 45 ms 332 KB Output is correct
11 Correct 45 ms 332 KB Output is correct
12 Correct 49 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 3 ms 332 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 27 ms 4524 KB Output is correct
2 Correct 35 ms 4512 KB Output is correct
3 Correct 36 ms 4420 KB Output is correct
4 Correct 3 ms 460 KB Output is correct
5 Correct 3 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 4452 KB Output is correct
10 Correct 26 ms 4420 KB Output is correct
11 Correct 30 ms 4472 KB Output is correct
12 Correct 30 ms 4516 KB Output is correct
13 Correct 27 ms 4412 KB Output is correct
14 Correct 30 ms 4752 KB Output is correct
# 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 3404 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 25 ms 4420 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 23 ms 4376 KB Output is correct
9 Correct 23 ms 4460 KB Output is correct
10 Correct 25 ms 4420 KB Output is correct
11 Correct 24 ms 4428 KB Output is correct
12 Correct 24 ms 4520 KB Output is correct
13 Correct 0 ms 332 KB Output is correct
14 Correct 0 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 0 ms 332 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 24 ms 4684 KB Output is correct
20 Correct 30 ms 4500 KB Output is correct
21 Correct 24 ms 4444 KB Output is correct
22 Correct 27 ms 4404 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 4 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 3 ms 332 KB Output is correct
4 Correct 3 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 0 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 45 ms 332 KB Output is correct
11 Correct 45 ms 332 KB Output is correct
12 Correct 49 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 3 ms 332 KB Output is correct
17 Correct 27 ms 4524 KB Output is correct
18 Correct 35 ms 4512 KB Output is correct
19 Correct 36 ms 4420 KB Output is correct
20 Correct 3 ms 460 KB Output is correct
21 Correct 3 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 4452 KB Output is correct
26 Correct 26 ms 4420 KB Output is correct
27 Correct 30 ms 4472 KB Output is correct
28 Correct 30 ms 4516 KB Output is correct
29 Correct 27 ms 4412 KB Output is correct
30 Correct 30 ms 4752 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 3404 KB Output is correct
34 Correct 1 ms 332 KB Output is correct
35 Correct 25 ms 4420 KB Output is correct
36 Correct 1 ms 332 KB Output is correct
37 Correct 0 ms 332 KB Output is correct
38 Correct 23 ms 4376 KB Output is correct
39 Correct 23 ms 4460 KB Output is correct
40 Correct 25 ms 4420 KB Output is correct
41 Correct 24 ms 4428 KB Output is correct
42 Correct 24 ms 4520 KB Output is correct
43 Correct 0 ms 332 KB Output is correct
44 Correct 0 ms 332 KB Output is correct
45 Correct 1 ms 332 KB Output is correct
46 Correct 1 ms 332 KB Output is correct
47 Correct 0 ms 332 KB Output is correct
48 Correct 0 ms 332 KB Output is correct
49 Correct 24 ms 4684 KB Output is correct
50 Correct 30 ms 4500 KB Output is correct
51 Correct 24 ms 4444 KB Output is correct
52 Correct 27 ms 4404 KB Output is correct
53 Correct 27 ms 4300 KB Output is correct
54 Correct 30 ms 4356 KB Output is correct
55 Correct 29 ms 4440 KB Output is correct
56 Correct 3 ms 332 KB Output is correct
57 Correct 2 ms 332 KB Output is correct
58 Correct 122 ms 3416 KB Output is correct
59 Correct 134 ms 4188 KB Output is correct
60 Correct 122 ms 4196 KB Output is correct
61 Correct 103 ms 4256 KB Output is correct
62 Correct 126 ms 4224 KB Output is correct
63 Correct 126 ms 4156 KB Output is correct
64 Correct 129 ms 4512 KB Output is correct
65 Correct 120 ms 4568 KB Output is correct
66 Correct 102 ms 4420 KB Output is correct
67 Correct 19 ms 3960 KB Output is correct
68 Correct 29 ms 5516 KB Output is correct
69 Correct 26 ms 5556 KB Output is correct
70 Correct 30 ms 5556 KB Output is correct
71 Correct 29 ms 5504 KB Output is correct
72 Correct 28 ms 5656 KB Output is correct
73 Correct 28 ms 5580 KB Output is correct
74 Correct 29 ms 5572 KB Output is correct