#include <bits/stdc++.h> using namespace std; #define pb push_back #define int long long const int MOD = 1e9 + 7; const int INF = 1e15; const int N = 1e6; int n, m, k, a, b, c, d, h, l, r, q, u, v, x, y; int s, e; vector<int> arr(N); vector<set<int>> adj(N); vector<bool> vis(N); map<pair<int, int>, int> weight; set<int> shops; bool found = 0; void dfs(int node, int d) { if(found) return; vis[node] = 1; // cout << node << " "; if(node==e) { // cout << node << " "; found = true; return; } if(shops.find(node) != shops.end()) { c = min(c, d); // cout << c << " "; } for(auto j : adj[node]) { if(!vis[j]) { dfs(j, d+weight[{node, j}]); } } } void solve() { cin >> n >> s >> q >> e; vector<pair<int, int>> edges(n+1); for(int i = 1; i<n; i++) { cin >> a >> b >> c; adj[a].insert(b); adj[b].insert(a); weight[{a, b}] = c; weight[{b, a}] = c; edges[i] = {a, b}; } for(int i = 0; i<s; i++) { cin >> a; shops.insert(a); } while(q--) { cin >> l >> r; adj[edges[l].first].erase(edges[l].second); adj[edges[l].second].erase(edges[l].first); c = INF; found = 0; dfs(r, 0); if(found) cout << "escaped"; else if(c == INF) { cout << "oo"; } else { cout << c; } cout << "\n"; adj[edges[l].first].insert(edges[l].second); adj[edges[l].second].insert(edges[l].first); for(int i = 1; i<=n; i++) vis[i] = 0; } } int32_t main() { ios::sync_with_stdio(false); cout.tie(0); cin.tie(0); int tc = 1; // cin >> tc; while(tc--) { solve(); cout << "\n"; } return 0; }