oj.uz

Submission #1088785

# Submission time Handle Problem Language Result Execution time Memory
1088785 2024-09-15T05:09:22 Z _callmelucian Olympic Bus (JOI20_ho_t4) C++14
100 / 100
 333 ms 4956 KB 
/*
    If you're looking at my code for solution,
    your brute-force code with a bit optimization is the solution.
*/

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pl;
typedef pair<int,int> pii;
typedef tuple<int,int,int> tt;

#define all(a) a.begin(), a.end()
#define filter(a) a.erase(unique(all(a)), a.end())

const int E = 5e4 + 4;
const int mn = 202;

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

int direct[E], a[E], b[E], cost[E], revCost[E], n;
ll distanc[mn][mn], dist[mn];
vector<tt> adj[mn];
bool vis[mn];

ll dijkstra (int s, int t) {
    for (int i = 1; i <= n; i++) dist[i] = LLONG_MAX, vis[i] = 0;
    dist[s] = 0;

    priority_queue<pl> pq; pq.emplace(0, s);
    while (pq.size()) {
        int u = pq.top().second; pq.pop();
        if (vis[u]) continue;
        if (u == t) return dist[t];
        vis[u] = 1;
        for (tt it : adj[u]) {
            int v, id, way; tie(v, id, way) = it;
            if (way != direct[id]) continue;
            if (dist[u] + cost[id] < dist[v]) {
                dist[v] = dist[u] + cost[id];
                pq.emplace(-dist[v], v);
            }
        }
    }
    return LLONG_MAX;
}

ll add (ll a, ll b) {
    return (max(a, b) == LLONG_MAX ? LLONG_MAX : a + b);
}

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

    int m; cin >> n >> m;
    for (int i = 1; i <= n; i++)
        for (int j = 1; j <= n; j++)
            distanc[i][j] = (i == j ? 0 : LLONG_MAX);

    for (int i = 0; i < m; i++) {
        cin >> a[i] >> b[i] >> cost[i] >> revCost[i];
        adj[a[i]].emplace_back(b[i], i, 0);
        adj[b[i]].emplace_back(a[i], i, 1);
        distanc[a[i]][b[i]] = min(distanc[a[i]][b[i]], (ll)cost[i]);
    }

    for (int k = 1; k <= n; k++)
        for (int i = 1; i <= n; i++)
            for (int j = 1; j <= n; j++)
                distanc[i][j] = min(distanc[i][j], add(distanc[i][k], distanc[k][j]));

    vector<int> cand(m);
    for (int i = 0; i < m; i++) cand[i] = i;
    shuffle(all(cand), rng);

    ll ans = add(distanc[1][n], distanc[n][1]);
    for (int i : cand) {
        ll tryOTN = min(distanc[1][n], add(add(distanc[1][b[i]], cost[i]), distanc[a[i]][n]));
        ll tryNTO = min(distanc[n][1], add(add(distanc[n][b[i]], cost[i]), distanc[a[i]][1]));
        if (add(add(tryOTN, tryNTO), revCost[i]) < ans) { // only optimize when possible
            direct[i] = 1;
            ll dist = add(dijkstra(1, n), dijkstra(n, 1));
            ans = min(ans, add(dist, revCost[i]));
            direct[i] = 0;
        }
    }
    cout << (ans == LLONG_MAX ? -1 : ans);

    return 0;
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 860 KB Output is correct
2 Correct 9 ms 828 KB Output is correct
3 Correct 11 ms 860 KB Output is correct
4 Correct 9 ms 900 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 9 ms 604 KB Output is correct
7 Correct 0 ms 344 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 12 ms 860 KB Output is correct
11 Correct 17 ms 912 KB Output is correct
12 Correct 10 ms 860 KB Output is correct
13 Correct 10 ms 860 KB Output is correct
14 Correct 9 ms 860 KB Output is correct
15 Correct 9 ms 860 KB Output is correct
16 Correct 9 ms 900 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 4432 KB Output is correct
2 Correct 22 ms 4444 KB Output is correct
3 Correct 23 ms 4708 KB Output is correct
4 Correct 10 ms 856 KB Output is correct
5 Correct 9 ms 744 KB Output is correct
6 Correct 9 ms 600 KB Output is correct
7 Correct 9 ms 832 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 26 ms 4532 KB Output is correct
10 Correct 27 ms 4764 KB Output is correct
11 Correct 23 ms 4700 KB Output is correct
12 Correct 22 ms 4836 KB Output is correct
13 Correct 23 ms 4944 KB Output is correct
14 Correct 26 ms 4956 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 860 KB Output is correct
2 Correct 9 ms 828 KB Output is correct
3 Correct 19 ms 3672 KB Output is correct
4 Correct 9 ms 604 KB Output is correct
5 Correct 22 ms 4428 KB Output is correct
6 Correct 0 ms 480 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 28 ms 4436 KB Output is correct
9 Correct 28 ms 4444 KB Output is correct
10 Correct 23 ms 4444 KB Output is correct
11 Correct 22 ms 4448 KB Output is correct
12 Correct 24 ms 4696 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 21 ms 4700 KB Output is correct
20 Correct 22 ms 4436 KB Output is correct
21 Correct 25 ms 4436 KB Output is correct
22 Correct 23 ms 4444 KB Output is correct

Subtask #4
63.0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 860 KB Output is correct
2 Correct 9 ms 828 KB Output is correct
3 Correct 11 ms 860 KB Output is correct
4 Correct 9 ms 900 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 9 ms 604 KB Output is correct
7 Correct 0 ms 344 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 12 ms 860 KB Output is correct
11 Correct 17 ms 912 KB Output is correct
12 Correct 10 ms 860 KB Output is correct
13 Correct 10 ms 860 KB Output is correct
14 Correct 9 ms 860 KB Output is correct
15 Correct 9 ms 860 KB Output is correct
16 Correct 9 ms 900 KB Output is correct
17 Correct 21 ms 4432 KB Output is correct
18 Correct 22 ms 4444 KB Output is correct
19 Correct 23 ms 4708 KB Output is correct
20 Correct 10 ms 856 KB Output is correct
21 Correct 9 ms 744 KB Output is correct
22 Correct 9 ms 600 KB Output is correct
23 Correct 9 ms 832 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 26 ms 4532 KB Output is correct
26 Correct 27 ms 4764 KB Output is correct
27 Correct 23 ms 4700 KB Output is correct
28 Correct 22 ms 4836 KB Output is correct
29 Correct 23 ms 4944 KB Output is correct
30 Correct 26 ms 4956 KB Output is correct
31 Correct 10 ms 860 KB Output is correct
32 Correct 9 ms 828 KB Output is correct
33 Correct 19 ms 3672 KB Output is correct
34 Correct 9 ms 604 KB Output is correct
35 Correct 22 ms 4428 KB Output is correct
36 Correct 0 ms 480 KB Output is correct
37 Correct 0 ms 348 KB Output is correct
38 Correct 28 ms 4436 KB Output is correct
39 Correct 28 ms 4444 KB Output is correct
40 Correct 23 ms 4444 KB Output is correct
41 Correct 22 ms 4448 KB Output is correct
42 Correct 24 ms 4696 KB Output is correct
43 Correct 0 ms 348 KB Output is correct
44 Correct 0 ms 348 KB Output is correct
45 Correct 0 ms 348 KB Output is correct
46 Correct 1 ms 348 KB Output is correct
47 Correct 0 ms 348 KB Output is correct
48 Correct 0 ms 348 KB Output is correct
49 Correct 21 ms 4700 KB Output is correct
50 Correct 22 ms 4436 KB Output is correct
51 Correct 25 ms 4436 KB Output is correct
52 Correct 23 ms 4444 KB Output is correct
53 Correct 21 ms 4268 KB Output is correct
54 Correct 23 ms 4324 KB Output is correct
55 Correct 29 ms 4256 KB Output is correct
56 Correct 9 ms 856 KB Output is correct
57 Correct 10 ms 664 KB Output is correct
58 Correct 25 ms 3628 KB Output is correct
59 Correct 29 ms 3672 KB Output is correct
60 Correct 30 ms 3668 KB Output is correct
61 Correct 20 ms 3676 KB Output is correct
62 Correct 106 ms 3772 KB Output is correct
63 Correct 231 ms 3848 KB Output is correct
64 Correct 64 ms 4224 KB Output is correct
65 Correct 180 ms 4348 KB Output is correct
66 Correct 333 ms 4300 KB Output is correct
67 Correct 10 ms 3020 KB Output is correct
68 Correct 32 ms 4692 KB Output is correct
69 Correct 33 ms 4824 KB Output is correct
70 Correct 23 ms 4424 KB Output is correct
71 Correct 23 ms 4444 KB Output is correct
72 Correct 27 ms 4576 KB Output is correct
73 Correct 24 ms 4752 KB Output is correct
74 Correct 23 ms 4688 KB Output is correct