Submission #890954

#	Time	Username	Problem	Language	Result	Execution time	Memory
890954		NeroZein	사이버랜드 (APIO23_cyberland)	C++17	100 / 100	1505 ms	101968 KiB

cyberland

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

using namespace std; 

using key = pair<double, int>; 

double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr) {
  K = min(K, 100); 
  vector<vector<pair<int, int>>> g(N);
  for (int i = 0; i < M; ++i) {
    g[x[i]].emplace_back(y[i], c[i]);
    g[y[i]].emplace_back(x[i], c[i]); 
  }
  vector<bool> reachable(N, 0);
  function<void(int)> dfs = [&](int v) {
    if (reachable[v]) return;
    reachable[v] = true;
    if (v == H) return;
    for (auto [u, _] : g[v]) {
      dfs(u); 
    }
  };
  dfs(0);
  priority_queue<key, vector<key>, greater<key>> pq;
  vector<vector<double>> dp(N, vector<double> (K + 2, -1)); 
  for (int k = 0; k <= K; ++k) {
    for (int i = 0; i < N; ++i) {
      if (i == 0 || (reachable[i] && arr[i] == 0)) {
        dp[i][k] = 0; 
      }
      if (dp[i][k] != -1) {
        pq.emplace(dp[i][k], i); 
      }
    }
    while (!pq.empty()) {
      auto [cost, v] = pq.top();
      pq.pop(); 
      if (cost != dp[v][k] || v == H) {
        continue; 
      }
      for (auto [u, w] : g[v]) {
        double nc = cost + w; 
        if (dp[u][k] == -1 || nc < dp[u][k]) {
          dp[u][k] = nc;
          pq.emplace(dp[u][k], u);
        }
        if (arr[u] == 2) {
          nc = nc / 2.0; 
          if (dp[u][k + 1] == -1 || nc < dp[u][k + 1]) {
            dp[u][k + 1] = nc;
          }
        }
      }
    }
  }
  double ans = -1; 
  for (int i = 0; i <= K; ++i) {
    if (dp[H][i] != -1 && (ans == -1 || ans > dp[H][i])) {
      ans = dp[H][i];
    }
  }
  if (reachable[H]) assert(ans != -1);
  else assert(ans == -1); 
  return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 13 / 13
• Subtask 4: 19 / 19
• Subtask 5: 7 / 7
• Subtask 6: 16 / 16
• Subtask 7: 29 / 29
• Subtask 8: 3 / 3