#include <bits/stdc++.h>
#include "cyberland.h"
#include <vector>
using namespace std;
using ll = long long;
const ll INF = 1e16;
vector<vector<ll> > adjList;
map<pair<ll, ll>, ll> weightMat;
vector<bool> isReachable;
double dijkstras(ll startingNode, vector<int> &A) {
ll N = adjList.size();
priority_queue<pair<ll, ll>, vector<pair<ll, ll> >, greater<pair<ll, ll> > > pq;
pq.push({0, startingNode});
// check if H is actually reachable to 0
vector<ll> distances(N, INF);
vector<bool> visited(N, false);
distances[startingNode] = 0;
while (!pq.empty()) {
auto [currentDistance, currentNode] = pq.top();
pq.pop();
if (visited[currentNode]) {
continue;
}
visited[currentNode] = true;
for (ll v: adjList[currentNode]) {
double newDist = currentDistance + weightMat[{currentNode, v}];
if (newDist < distances[v]) {
distances[v] = newDist;
pq.push({distances[v], v});
}
}
}
ll minimumPossible = distances[0];
for (ll i = 0; i < N; i++) {
if ((A[i] == 0) && isReachable[i])
minimumPossible = min(minimumPossible, distances[i]);
}
return (double)(minimumPossible);
}
double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr) {
adjList.clear();
weightMat.clear();
adjList.resize(N);
for (ll i = 0; i < M; i++) {
adjList[x[i]].push_back(y[i]);
adjList[y[i]].push_back(x[i]);
weightMat[{x[i], y[i]}] = (double)c[i];
weightMat[{y[i], x[i]}] = (double)c[i];
}
isReachable.resize(N, false);
queue<ll> q; q.push(0);
while (!q.empty()) {
ll currentTop = q.front();
q.pop();
if (isReachable[currentTop]) continue;
isReachable[currentTop] = true;
if (currentTop == H) break;
for (auto v: adjList[currentTop]) {
q.push(v);
}
}
if (!isReachable[H]) {
return -1;
}
double response = dijkstras(H, arr);
if (response >= INF) {
return -1.0;
} else {
return response;
}
}
