#include "bits/stdc++.h"
using namespace std;
#define ff first
#define ss second
#define all(v) v.begin(), v.end()
#define ll long long
#define pb push_back
#define pii pair<int, int>
#define wr puts("----------------")
template<class T>bool umin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool umax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
const int N = 1e5+5;
vector<pii> adj[N];
int a[N];
ll dis[N];
void dfs(int x, int pr = -1){
for(auto [i, w] : adj[x])
if(i != pr){
dis[i] = dis[x]+w;
if(a[i] == 0)
dis[i] = 0;
dfs(i, x);
}
}
double solve(int n, int m, int k, int h, vector<int> u, vector<int> v, vector<int> w, vector<int> arr){
for(int i = 0; i < n; ++i)
a[i] = arr[i];
for(int i = 0; i < m; ++i){
adj[u[i]].pb({v[i], w[i]});
adj[v[i]].pb({u[i], w[i]});
}
for(int i = 0; i <= n; ++i)
dis[i] = 0;
// I will make 0 root
dfs(0);
// you can always go to the h from the root(0), because this is tree
double answer = 0;
answer += dis[h];
for(int i = 0; i <= n; ++i)
adj[i].clear();
return answer;
}
