Submission #970928

#	Time	Username	Problem	Language	Result	Execution time	Memory
970928		mannshah1211	Cyberland (APIO23_cyberland)	C++17	97 / 100	3066 ms	94372 KiB

cyberland

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

using namespace std;

using state = tuple<double, int, int>;

const double eps = 1e-9;
const double inf = 1e14;

double solve(int n, int m, int k, int h, vector<int> x, vector<int> y, vector<int> c, vector<int> a) {
  k = min(k, 70);
  vector<vector<double>> d(n, vector<double>(k + 1, inf));
  vector<vector<pair<int, int>>> g(n);
  for (int i = 0; i < m; i++) {
    g[x[i]].push_back(make_pair(y[i], c[i]));
    g[y[i]].push_back(make_pair(x[i], c[i]));
  }
  d[0][0] = 0;
  priority_queue<state, vector<state>, greater<state>> pq;
  pq.push({0, 0, 0});
  while (!pq.empty()) {
    auto [expected, who, used] = pq.top();
    pq.pop();
    if (d[who][used] - expected < -eps) {
      continue;
    }
    if (who == h) {
      continue;
    }
    for (auto [to, w] : g[who]) {
      if (a[to] == 1) {
        if (d[to][used] > expected + w) {
          d[to][used] = expected + w;
          pq.push({d[to][used], to, used});
        }
      } else if (a[to] == 2) {
        if (used <= k - 1 && d[to][used + 1] > ((expected + (double) w) / 2)) {
          d[to][used + 1] = (expected + (double) w) / 2;
          pq.push({d[to][used + 1], to, used + 1});
        }
        if (d[to][used] > expected + w) {
          d[to][used] = expected + w;
          pq.push({d[to][used], to, used});
        }
      } else {
        if (d[to][used] > 0) {
          d[to][used] = 0;
          pq.push({0, to, used});
        }
      }
    }
  }
  double cur = d[h][0];
  for (int i = 0; i <= k; i++) {
    if (cur > d[h][i]) {
      cur = d[h][i];
    }
  }
  if (abs(cur - inf) < eps) {
    return -1;
  }
  return cur;
}

• 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: 0 / 3