//In the name of GOD***---...---***---...---***---...
/*/=======================================
Diversity in counsel, unity in command
__
Success always calls for greater generosity - though
most people, lost in the darkness of their own egos,
treat it as an occasion for greater greed.
Collecting boot is not an end itself, but only a means for
building an empire. Riches would be of little use to us now
except as a means of winning new friends.
__*By Cyrus the great*__
=======================================/*/
#include<bits/stdc++.h>
using namespace std;
////========== Defines ==============////
#define IOS ios_base::sync_with_stdio(0);\
cin.tie(0);\
cout.tie(0);
#define F first
#define S second
#define mp make_pair
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define fixed(a) fixed<<setprecision(a)
////=============== Typedefs ==============////
typedef long long int lli;
typedef pair<int,int> pii;
////=============== CONSTANT ===============////
const lli mx = (1e3+100)*5, inf = (1<<30);
////============== Global types ============////
vector<pii> adj[mx];
int n, s, q, e, mini =inf, ban1, ban2;
pii ed[mx];
int wi[mx][mx], st[mx], dis[mx];
////========== User Define Functions ==========////
void dfs(int p, int v){
// cout << v << '\n';
if(v == e) mini = -1;
dis[v] =dis[p] + wi[p][v];
if(st[v] == 1) {
mini = min(mini, dis[v]);
}
for(auto u : adj[v]) if(!(u.F == p || (v == ban1 && u.F == ban2) || (v == ban2 && u.F == ban1))) dfs(v, u.F);
}
void solve(int ban, int pos) {
mini =inf;
// if(n == s){
// if(pos == e) cout << 0 << '\n';
// else cout << "escaped\n";
// }
// else{
dfs(0, pos);
if(mini == -1){
cout << "escaped\n";
return;
}
if(mini == inf){
cout << "oo";
return;
}
cout << mini << '\n';
// }
}
////================= Notes =================////
/*
*/
////============ End of Templates ============////
int main() {
IOS
cin >> n >> s >> q >> e;
for(int i =1; i <= n-1; i++) {
int x, y, w;
cin >> x >> y >> w;
ed[i] = mp(x, y);
wi[x][y] = w;
wi[y][x] =w;
adj[x]. pb(mp(y, w));
adj[y]. pb(mp(x, w));
}
for(int i =0; i < s; i++) {
int x; cin >> x;
st[x] =1;
}
while(q--){
int ban, pos;
cin >> ban >> pos;
ban1 = ed[ban].F; ban2 = ed[ban].S;
solve(ban, pos);
}
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
return 0;
}
//Hewwo OwO
