Submission #919548

#	Time	Username	Problem	Language	Result	Execution time	Memory
919548		dosts	Cyberland (APIO23_cyberland)	C++17	97 / 100	3040 ms	63468 KiB

cyberland

#pragma GCC optimize("O3,unroll-loops")
#include "cyberland.h"
#include <bits/stdc++.h>
using namespace std;
 
vector<pair<int,int>> edges[100000];
 
double solve(int N, int M, int K, int H, std::vector<int> x, std::vector<int> y, std::vector<int> c, std::vector<int> arr) {
    K = min(K,68);
    for (int i=0;i<N;i++) edges[i].clear();
    for (int i=0;i<M;i++) {
        edges[x[i]].push_back({y[i],c[i]});
        edges[y[i]].push_back({x[i],c[i]});
    }
    int ARR[arr.size()];
    for (int i=0;i<arr.size();i++) ARR[i] = arr[i];
    double dp[N][K+1];
    for (int i=0;i<N;i++) {
        for (int j=0;j<=K;j++) dp[i][j] = 2e18;
    }
    priority_queue<pair<double,pair<int,int>>,vector<pair<double,pair<int,int>>>,greater<pair<double,pair<int,int>>>> pq;
    dp[0][0] = 0;
    pq.push({0,{0,0}});
    while (!pq.empty()) {
        pair<double,pair<int,int>> f = pq.top();
        pq.pop();
        double cost = f.first;
        int used = f.second.second;
        int city = f.second.first;
        if (dp[city][used] < cost) continue;
        if (used && dp[city][used-1] < cost) {
            dp[city][used] = dp[city][used-1];
            continue;
        }
        if (city == H) continue;
        for (auto it : edges[city]) {
            int dest = it.first;
            int go = it.second; 
            if (!ARR[dest]) {
                if (dp[dest][used]>0) {
                    pq.push({0,{dest,used}});
                    dp[dest][used] = 0;
                }
            }
            else {
                if (dp[dest][used] > cost+go) {
                    pq.push({cost+go,{dest,used}}); 
                    dp[dest][used] = cost+go;
                }               
                if (ARR[dest] == 2) {
                    if (dp[dest][used+1] > (cost+go)/2 && used!=K) {
                        pq.push({(cost+go)/2,{dest,used+1}});
                        dp[dest][used+1] = (cost+go)/2;
                    }
                }
            }
        }
    }
    double ans = 2e18;
    for (int i=0;i<=K;i++) ans = min(ans,dp[H][i]);
    return ans==2e18?-1:ans;
}

Compilation message (stderr)

cyberland.cpp: In function 'double solve(int, int, int, int, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
cyberland.cpp:16:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for (int i=0;i<arr.size();i++) ARR[i] = arr[i];
      |                  ~^~~~~~~~~~~

• 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