#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "cyberland.h"
namespace DANDAX {
typedef vector<vector<pair<int, ld>>> GRAPH;
int n, m, k, h;
GRAPH gp;
VI col;
typedef vector<ld> VD;
typedef vector<VD> VVD;
double sol(int N, int M, int K, int H, VI X, VI Y, VI C, VI ARR) {
n = N, m = M, k = K, h = H;
col = ARR;
gp = GRAPH(n * (k+1));
rep(i, m) {
int u = X[i];
int v = Y[i];
ld w = C[i];
gp[u].pb({v, w});
gp[v].pb({u, w});
replr(l, 0, k) {
gp[u + n*l].pb({v + n*l, w});
gp[v + n*l].pb({u + n*l, w});
w /= 2;
}
}
ld ans = 1e18;
VD cur(n, 1e18);
cur[0] = 0;
for (int i = 0; i < 10; i++) {
VD nxt(n, 1e18);
rep(u, n) if (u != h) {
for (auto[v, w] : gp[u]) {
setmin(nxt[v], cur[u] + w);
}
}
rep(u, n) if (col[u] == 2) if (nxt[u] != 1e18) nxt[u] /= 2;
rep(u, n) if (col[u] == 0) if (nxt[u] != 1e18) nxt[u] = 0;
cur = nxt;
setmin(ans, cur[h]);
}
if (ans == 1e18) return -1;
return ans;
}
}
typedef vector<vector<pair<int, ld>>> GRAPH;
int n, h;
void dijkstra(GRAPH& gp, vector<ld>& dist, int s) {
int n = gp.size();
priority_queue<pair<ld, int>> pq;
dist = vector<ld>(n, 1e18);
dist[s] = 0;
pq.push({0, s});
VI vis(n);
while (pq.size()) {
int u = pq.top().ss;
pq.pop();
if (vis[u]) continue;
vis[u] = true;
for (auto[v, w] : gp[u]) {
if (v%(::n) == h) continue;
if (dist[u] + w < dist[v]) {
dist[v] = dist[u] + w;
pq.push({-dist[v], v});
}
}
}
}
int m, k;
GRAPH gp;
VI col;
ld ans;
VI vis;
void dfs(int u, vector<ld>& dist) {
if (u%n == h) return;
if (col[u%n] == 0) setmin(ans, dist[u]);
vis[u] = true;
for (auto[v, w] : gp[u]) if (!vis[v]) dfs(v, dist);
}
double solve(int N, int M, int K, int H, VI X, VI Y, VI C, VI ARR) {
n = N, m = M, k = K, h = H;
setmin(K, 31);
col = ARR;
gp = GRAPH(n * (k+1));
rep(i, m) {
int u = X[i];
int v = Y[i];
ld w = C[i];
replr(l, 0, k) {
gp[u + n*l].pb({v + n*l, w});
gp[v + n*l].pb({u + n*l, w});
w /= 2;
}
}
rep(u, n) if (col[u] == 2) {
ld dv = 2;
replr(l, 0, k-1) {
for (auto[v, w] : gp[u]) if (v < n) {
gp[u + l*n].pb({v + n*(l+1), w/dv});
/* cout << "KOX: " << u + l*n << " " << v + n*(l+1) << " " << w/dv << endl; */
}
dv *= 2;
}
}
vector<ld> dist;
dijkstra(gp, dist, h);
/* for (ld x : dist) cout << x << " "; */
/* cout << endl; */
if (dist[0] == 1e18) return -1;
col[0] = 0;
vis = VI(gp.size());
ans = 1e18;
dfs(0, dist);
return ans;
}
