#include "cyberland.h"
#include <bits/stdc++.h>
using namespace std;
vector<vector<double>> dp;
vector<vector<pair<int, int>>> adjlist;
vector<int> type;
int maxk;
int target;
void recur(int node, int curk, double curw)
{
if (type[node] == 0)
curw = 0;
else if (type[node] == 2)
{
if (curw < dp[node][curk])
{
dp[node][curk] = curw;
if (node == target)
return;
for (auto a : adjlist[node])
recur(a.first, curk, curw + a.second);
}
curw /= 2;
curk++;
}
if (curk > maxk)
return;
if (curw < dp[node][curk])
{
dp[node][curk] = curw;
if (node == target)
return;
for (auto a : adjlist[node])
recur(a.first, curk, curw + a.second);
}
}
double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr)
{
K = 30;
maxk = K;
target = H;
type = arr;
dp.clear();
adjlist.clear();
adjlist.resize(N);
for (int i = 0; i < M; i++)
adjlist[x[i]].push_back({y[i], c[i]}), adjlist[y[i]].push_back({x[i], c[i]});
dp.resize(N);
for (auto &a : dp)
a.resize(K + 1, 1e15);
recur(0, 0, 0);
double mini = 1e15;
for (int i = 0; i <= K; i++)
mini = min(mini, dp[H][i]);
if (mini == 1e15)
return -1;
return mini;
}
