#include "cyberland.h"
#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define pdi pair<double,int>
#define fi first
#define se second
const double inf=1e18;
double solve(int N, int M, int K, int T, std::vector<int> x, std::vector<int> y, std::vector<int> c, std::vector<int> arr) {
K=min(K,67);
vector<vector<double>> dist(N,vector<double>(K+1,inf));
vector<vector<pii>> edge(N);
for(int i=0;i<M;i++){
edge[x[i]].push_back({y[i],c[i]});
edge[y[i]].push_back({x[i],c[i]});
}
vector<int> vis(N,0);
dist[0][0]=0;vis[0]=1;
queue<int> q;q.push(0);
while(!q.empty()){
int u=q.front();q.pop();
if(arr[u]==0) dist[u][0]=0;
if(u==T) continue;
for(auto [v,w]:edge[u]){
if(vis[v]) continue;
vis[v]=1;q.push(v);
}
}
bool ok=false;
double res=1e14;
for(int k=0;k<=K;k++){
priority_queue<pdi,vector<pdi>,greater<pdi>> pq;
for(int i=0;i<N;i++){
if(i!=T && dist[i][k]!=inf) pq.push({dist[i][k],i});
}
while(!pq.empty()){
auto [d,u]=pq.top();pq.pop();
if(u==T) continue;
if(d!=dist[u][k]) continue;
for(auto [v,w]:edge[u]){
if(arr[u]==2 && k!=K) dist[v][k+1]=min(dist[v][k+1],dist[u][k]/2+w);
if(dist[u][k]+w<dist[v][k]){
dist[v][k]=dist[u][k]+w;
pq.push({dist[u][k]+w,v});
}
}
}
if(dist[T][k]!=inf) ok=true;
res=min(res,dist[T][k]);
}
if(ok) return res;
else return -1;
}
