Submission #589813

#	Time	Username	Problem	Language	Result	Execution time	Memory
589813		Sam_a17	Shortcut (IOI16_shortcut)	C++14	0 / 100	2089 ms	596 KiB

shortcut

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include "shortcut_c.h"
#include <cstdio>
using namespace std;
#define ll long long

const int N = 6e3 + 10;
const ll inf = 1e16;
multiset<pair<ll, long long>> adj[N];
int ni;

pair<long long, long long> djik(int node) {
  vector<bool> used(ni + 1);
  vector<long long> dist(ni + 1, inf);
  priority_queue<pair<ll, ll>, vector<pair<ll, ll>> , greater<pair<ll, ll>> > q;
  dist[node] = 0;
  q.push({0, node});
 
  while(!q.empty()) {
    auto u = q.top();
    q.pop();

    if(used[u.second]) {
      continue;
    }
    used[u.second] = true;

    for(auto i: adj[u.second]) {
      if(dist[i.first] > dist[u.second] + i.second) {
        dist[i.first] = dist[u.second] + i.second;
        q.push({dist[i.first], i.first});
      }
    }
  }

  pair<ll, ll> answ = {-1, -1};

  for(int i = 0; i < ni; i++) {
    if(dist[i] == inf) {
      assert(false);
    }

    if(dist[i] > answ.first) {
      answ = {dist[i], i};
    }
  }

  return answ;
}

long long find_shortcut(int n, std::vector<int> l, std::vector<int> d, int c) {
  ni = n;

  if(d[0]) {
    adj[0].insert({ni, d[0]});
    adj[ni++].insert({0, d[0]});
  }

  for(int i = 1; i < n; i++) {

    adj[i - 1].insert({i, l[i - 1]});
    adj[i].insert({i - 1, l[i - 1]});

    if(d[i]) {
      adj[i].insert({ni, d[i]});
      adj[ni++].insert({i, d[i]});
    }
  }

  long long minDiametr = INT64_MAX;
  for(int i = 0; i < n; i++) {
    for(int j = i + 1; j < n; j++) {
      adj[i].insert({j, (long long)c});
      adj[j].insert({i, (long long)c});

      long long maxi = INT64_MIN;
      for(int k = 0; k < ni; k++) {
        maxi = max(maxi, djik(k).first);
      }

      minDiametr = min(maxi, minDiametr);

      adj[i].erase(adj[i].find(make_pair(j, (ll)c)));
      adj[j].erase(adj[j].find(make_pair(i, (ll)c)));
    }
  }

  return minDiametr;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 14
• Subtask 3: 0 / 8
• Subtask 4: 0 / 7
• Subtask 5: 0 / 33
• Subtask 6: 0 / 22
• Subtask 7: 0 / 4
• Subtask 8: 0 / 3