#include <bits/stdc++.h>
#include "cyberland.h"
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
using namespace std;
// #define int long long int
// const int N = 2e5 + 10;
// const int md = 1e9 + 7;
// const int INF = 1e18;
double solve(int n, int m, int k, int h, vector<int> x, vector<int> y, vector<int> w, vector<int> a) {
vector<vector<pair<int, int>>> g(n + 1, vector<pair<int, int>> ());
bool ok = 0;
for (int i = 0; i < m; i++) {
g[x[i]].push_back({y[i], w[i]});
g[y[i]].push_back({x[i], w[i]});
if (x[i] == y[i]) ok = 1;
}
if (ok) return -1;
vector<double> dist(g.size() + 10, 0);
vector<bool> visited(g.size() + 10);
set<pair<double, int>> q;
dist[h] = 0;
q.insert({0, h});
double ans = 0;
while (!q.empty()) {
int v = (*q.begin()).second;
if (!a[v]) {
ans = dist[v];
break;
}
q.erase(q.begin());
if (!visited[v])
for (auto i : g[v]) {
if (!dist[i.first])
dist[i.first] = dist[v] + i.second;
else dist[i.first] = min(dist[i.first], dist[v] + (double)i.second);
if (!visited[i.first])
q.insert({dist[i.first], i.first});
}
visited[v] = 1;
}
if (ans != 0) return ans;
else return dist[0];
}
// int32_t main(int32_t argc, char *argv[]) {
// ios::sync_with_stdio(false);
// cin.tie(nullptr);
// int T = 1;
// // cin >> T;
// while (T--) {
// cout << solve(4, 4, 30, 3, {0, 0, 1, 2}, {1, 2, 3, 3}, {5, 4, 2, 4}, {1, 0, 1, 1}) << '\n';
// }
// return 0;
// }
