Submission #410333

#	Time	Username	Problem	Language	Result	Execution time	Memory
410333		600Mihnea	Crocodile's Underground City (IOI11_crocodile)	C++17	46 / 100	30 ms	11088 KiB

crocodile

#include <bits/stdc++.h>
#include "crocodile.h"

using namespace std;

typedef long long ll;

const int N = 100000 + 7;
const int INF = (int) 1e9 + 7;
int n, m, k, best[N];
multiset<int> adj[N];
vector<pair<int, int>> g[N];
priority_queue<pair<int, int>> q;

void push(int i, int value) {
  best[i] = value;
  for (auto &it : g[i]) {
    adj[it.first].insert(min(INF, best[i] + it.second));
  }
  q.push({-best[i], i});
}

int get_second(int a) {
  if ((int) adj[a].size() < 2) {
    return INF;
  }
  auto it = adj[a].begin();
  it++;
  return *it;
}

int travel_plan(int nn, int mm, int r[][2], int len[], int kk, int ch[]) {
  n = nn;
  m = mm;
  k = kk;
  for (int i = 0; i < n; i++) {
    g[i].clear();
    adj[i].clear();
    best[i] = INF;
  }
  for (int i = 0; i < m; i++) {
    g[r[i][0]].push_back({r[i][1], len[i]});
    g[r[i][1]].push_back({r[i][0], len[i]});
    adj[r[i][0]].insert(INF);
    adj[r[i][1]].insert(INF);
  }
  for (int i = 0; i < k; i++) {
    push(ch[i], 0);
  }
  int cnt = 0;
  while (!q.empty()) {
    int a = q.top().second, o = -q.top().first;
    q.pop();
    if (best[a] != o) {
      continue;
    }
    for (auto &it : g[a]) {
      int node = it.first, relax = get_second(node);
      if (relax < best[node]) {
        push(node, relax);
      }
    }
  }
  if (best[0] == INF) {
    best[0] = -1;
  }
  return best[0];
}

Compilation message (stderr)

crocodile.cpp: In function 'int travel_plan(int, int, int (*)[2], int*, int, int*)':
crocodile.cpp:50:7: warning: unused variable 'cnt' [-Wunused-variable]
   50 |   int cnt = 0;
      |       ^~~

• Subtask 1: 46 / 46
• Subtask 2: 0 / 43
• Subtask 3: 0 / 11