Submission #656210

#	Time	Username	Problem	Language	Result	Execution time	Memory
656210		benjaminkleyn	Crocodile's Underground City (IOI11_crocodile)	C++17	100 / 100	564 ms	89276 KiB

crocodile

#include <bits/stdc++.h>
#include "crocodile.h"
using namespace std;
typedef long long ll;
 
int n;
vector<pair<int,ll>> g[100000];
ll dist[100000][2];
bool vis[100000];
 
void dijkstra(int K, int P[])
{
    for (int i = 0; i < n; i++)
    {
        dist[i][0] = dist[i][1] = LLONG_MAX; 
        vis[i] = false;
    }
 
    priority_queue<pair<ll,int>> pq;
    for (int i = 0; i < K; i++)
    {
        pq.push({0LL, P[i]});
        dist[P[i]][0] = dist[P[i]][1] = 0LL;
    }
 
    while (!pq.empty())
    {
        int u = pq.top().second;
        pq.pop();
        if (vis[u]) continue;
        vis[u] = true;
 
        for (auto [v, l] : g[u])
            if (!vis[v])
                if (dist[u][1] + l < dist[v][1])
                {
                    dist[v][1] = dist[u][1] + l;
                    if (dist[v][1] < dist[v][0])
                        swap(dist[v][0], dist[v][1]);
                    if (dist[v][1] != LLONG_MAX)
                        pq.push({-dist[v][1], v});
                }
    }
 
}
 
int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
    n = N;
    for (int i = 0; i < M; i++)
    {
        g[R[i][0]].push_back({R[i][1], L[i]});
        g[R[i][1]].push_back({R[i][0], L[i]});
    }
    dijkstra(K, P);
    return dist[0][1];
}

• Subtask 1: 46 / 46
• Subtask 2: 43 / 43
• Subtask 3: 11 / 11