#include "cyberland.h"
#include <vector>
#include <queue>
using namespace std;
typedef long long ll;
const ll INF = 1e18;
// Dijkstra's algorithm from USACO guide
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) {
vector<vector<pair<int, int>>> adj(N);
for (int i = 0; i < M; i++) {
adj[x[i]].push_back({y[i], c[i]});
adj[y[i]].push_back({x[i], c[i]});
}
using T = pair<ll, int>;
vector<bool> visited(N, false);
vector<ll> dist(N, INF);
dist[0] = 0;
priority_queue<T, vector<T>, greater<T>> pq;
pq.push({0, 0});
while (!pq.empty()) {
const auto [cdist, node] = pq.top();
pq.pop();
if (visited[node]) continue;
if (cdist != dist[node]) continue;
for (const pair<int, int> &i : adj[node]) {
// if (visited[i.first]) continue;
if (arr[i.first] == 0) {
pq.push({dist[i.first] = 0, i.first});
visited[i.first] = true;
continue;
}
if (cdist + i.second < dist[i.first]) {
pq.push({dist[i.first] = cdist + i.second, i.first});
}
}
}
return dist[H];
}
