Submission #958419

# Submission time Handle Problem Language Result Execution time Memory
958419 2024-04-05T18:57:53 Z BhavayGoyal Olympic Bus (JOI20_ho_t4) C++14
5 / 100
1000 ms 7172 KB
#include <bits/stdc++.h>
using namespace std;
 
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
 
template<class T> using oset = 
            tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
 
#define int long long
#define ld long double
#define ar array
#define vi vector<int>
#define vii vector<vector<int>>
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define f first
#define s second
#define endl "\n"
 
const int MOD = 1e9+7;
const int inf = 1e9;
const int linf = 1e15;
 
const int d4i[4]={-1, 0, 1, 0}, d4j[4]={0, 1, 0, -1};
const int d8i[8]={-1, -1, 0, 1, 1, 1, 0, -1}, d8j[8]={0, 1, 1, 1, 0, -1, -1, -1};
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
 
// -------------------------------------------------- Main Code --------------------------------------------------
 
const int N = 205, M = 50005;
int n, m, dist[N][N];
set<pii> g[N];
vii edges, shortestEdges;
map<pair<int, int>, bool> isShort;
map<pii, pii> edge;
 
pair<vi, vi> dijkstra(int source) {
    priority_queue<pii, vector<pii>, greater<>> q;
    vi vis(n+1, 0), dis(n+1, linf), par(n+1);
    q.push({0, source});
    dis[source] = 0;
    while (!q.empty()) {
        pii f = q.top(); q.pop();
        int src = f.s;
        if (vis[src]) continue;
        vis[src] = true;
 
        for (auto child : g[src]) {
            int ch = child.f, wt = child.s;
            if (dis[ch] > dis[src] + wt) {
                par[ch] = src;
                dis[ch] = dis[src] + wt;
                q.push({dis[ch], ch});
            }
        }
    }
    return {dis, par};
}
 
void sol() {
    for (int i = 0; i < N; i++) for (int j = 0; j < N; j++) dist[i][j] = linf;
 
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        int a, b, c, d; cin >> a >> b >> c >> d;
        dist[a][b] = c;
        edge[{a, b}] = {c, d};
        g[a].insert({b, c});
        edges.pb({a, b, c, d});
    }
 
    pair<vi, vi> x = dijkstra(1); vi dis = x.f, par = x.s;
    int c = n;
    while (par[c]) {
        pii temp = edge[{par[c], c}];
        shortestEdges.pb({par[c], c, temp.f, temp.s});
        isShort[{par[c], c}] = true;
        c = par[c];
    }
 
    x = dijkstra(n); dis = x.f, par = x.s;
    c = 1;
    while (par[c]) {
        pii temp = edge[{par[c], c}];
        shortestEdges.pb({par[c], c, temp.f, temp.s});
        isShort[{par[c], c}] = true;
        c = par[c];
    }
 
    for (int k = 1; k <= n; k++) {
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= n; j++) {
                if (i == j) dist[i][j] = 0;
                dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j]);
            }
        }
    }

    pair<vi, vi> xx = dijkstra(1);
    pair<vi, vi> yy = dijkstra(n);
    int ans = xx.f[n] + yy.f[1];

    for (auto i : edges) {
        int a = i[0], b = i[1], c = i[2], d = i[3];
        g[a].erase({b, c});
        g[b].insert({a, c});
        pair<vi, vi> x = dijkstra(1);
        pair<vi, vi> y = dijkstra(n);
        ans = min(ans, x.f[n] + y.f[1] + d);
        g[b].erase({a, c});
        g[a].insert({b, c});
    }
 
    cout << (ans>=1e10?-1:ans) << endl;
}
 
signed main () {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
 
    int t = 1;
    // cin >> t; 
    while (t--) {
        sol();
    }
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 36 ms 856 KB Output is correct
2 Correct 9 ms 860 KB Output is correct
3 Correct 53 ms 1040 KB Output is correct
4 Correct 58 ms 1028 KB Output is correct
5 Correct 17 ms 860 KB Output is correct
6 Correct 9 ms 876 KB Output is correct
7 Correct 0 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 14 ms 940 KB Output is correct
10 Correct 78 ms 860 KB Output is correct
11 Correct 78 ms 860 KB Output is correct
12 Correct 79 ms 1072 KB Output is correct
13 Correct 30 ms 1016 KB Output is correct
14 Correct 36 ms 856 KB Output is correct
15 Correct 32 ms 856 KB Output is correct
16 Correct 38 ms 1036 KB Output is correct
# Verdict Execution time Memory Grader output
1 Execution timed out 1036 ms 7172 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 35 ms 860 KB Output is correct
2 Correct 11 ms 860 KB Output is correct
3 Execution timed out 1097 ms 6932 KB Time limit exceeded
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 36 ms 856 KB Output is correct
2 Correct 9 ms 860 KB Output is correct
3 Correct 53 ms 1040 KB Output is correct
4 Correct 58 ms 1028 KB Output is correct
5 Correct 17 ms 860 KB Output is correct
6 Correct 9 ms 876 KB Output is correct
7 Correct 0 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 14 ms 940 KB Output is correct
10 Correct 78 ms 860 KB Output is correct
11 Correct 78 ms 860 KB Output is correct
12 Correct 79 ms 1072 KB Output is correct
13 Correct 30 ms 1016 KB Output is correct
14 Correct 36 ms 856 KB Output is correct
15 Correct 32 ms 856 KB Output is correct
16 Correct 38 ms 1036 KB Output is correct
17 Execution timed out 1036 ms 7172 KB Time limit exceeded
18 Halted 0 ms 0 KB -