#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// #include <ext/rope>
using namespace std;
// using namespace __gnu_pbds;
typedef long long ll;
typedef unsigned long long ull;
typedef unsigned int uint;
typedef long double ld;
template <class T>
using VV = vector<vector<T>>;
using VI = vector<int>;
using VVI = vector<vector<int>>;
using VL = vector<long long>;
using VVL = vector<vector<long long>>;
using VC = vector<char>;
using VVC = vector<vector<char>>;
using VB = vector<bool>;
using VVB = vector<vector<bool>>;
using VD = vector<double>;
using VVD = vector<vector<double>>;
using PII = pair<int, int>;
using PLL = pair<long long, long long>;
using PIL = pair<int, long long>;
using PLI = pair<long long, int>;
using VPII = vector<pair<int, int>>;
using VPLL = vector<pair<long long, long long>>;
#define LINE '\n'
#define SPACE ' '
#define PB push_back
#define FOR(i, a, b) for (int i = (a); i < (int(b)); i++)
#define FORE(i, a, b) for (int i = (a); i <= (int)((b)); i++)
#define ALL(x) x.begin(), x.end()
#define RALL(x) x.rbegin(), x.rend()
#define sq(a) ((a) * (a))
#define sz(x) ((int)x.size())
#define fastio() \
ios_base::sync_with_stdio(false); \
cin.tie(nullptr); \
cout.tie(nullptr)
#define debug(x) cerr << #x << " = " << x << endl;
const ll MOD = 1e9 + 7;
template <class T>
inline void maxi(T &a, T b)
{
a = max(a, b);
}
template <class T>
inline void mini(T &a, T b)
{
a = min(a, b);
}
template <class T>
inline void addi(T &a, T b)
{
a = (a + b) % MOD;
}
template <class T>
inline void subi(T &a, T b)
{
a = (a - b + MOD) % MOD;
}
template <class T>
inline T add(T a, T b)
{
return (a + b) % MOD;
}
template <class T>
inline T sub(T a, T b)
{
return (a - b + MOD) % MOD;
}
template <class T>
inline T mul(T a, T b)
{
return ((a % MOD) * (b % MOD)) % MOD;
}
constexpr ll binpow(ll a, ll b, ll mod)
{
ll res = 1;
while (b > 0)
{
if (b & 1)
{
res = (res * a) % mod;
}
a = (a * a) % mod;
b >>= 1;
}
return res;
}
const ll INF = 1e17;
const int MAX_N = 1e5 + 3;
const int d = 18;
vector<pair<int, ll>> g[MAX_N];
VB shop(MAX_N, false);
VI in(MAX_N, -1), out(MAX_N, -1);
VL sm(MAX_N, 0);
VL dpdown(MAX_N, INF);
VVL dp(MAX_N, VL(d + 1, INF));
VVL up(MAX_N, VL(d + 1, 0));
int t = 0;
void dfs(int c, int p)
{
if (shop[c])
dpdown[c] = 0;
in[c] = ++t;
for (auto [v, cost] : g[c])
{
if (v == p)
continue;
sm[v] = sm[c] + cost;
dfs(v, c);
mini(dpdown[c], dpdown[v] + cost);
}
out[c] = ++t;
}
bool isanc(int a, int b)
{
return in[a] <= in[b] && out[a] >= out[b];
}
void dlift(int c, int p)
{
dp[c][0] = min(dpdown[c], (sm[c] - sm[p]) + dpdown[p]); // edge c-p
up[c][0] = p;
FOR(i, 1, d + 1)
{
int u = up[c][i - 1];
up[c][i] = up[u][i - 1];
ll fr = dp[c][i - 1];
ll cost = sm[c] - sm[u]; // koszt na c-up[c][i-1]
ll sc = dp[u][i - 1] + cost;
dp[c][i] = min(fr, sc);
}
for (auto [v, _] : g[c])
{
if (v == p)
continue;
dlift(v, c);
}
}
void query(int road_bottom, int orig)
{
int c = orig;
if (!isanc(road_bottom, c))
{
cout << "escaped" << LINE;
return;
}
if(c == road_bottom) {
ll ans = dpdown[c];
cout << (ans >= INF ? "oo" : to_string(ans)) << LINE;
return;
}
ll ans = dpdown[c];
for (int i = d; i >= 0; i--)
{
if (isanc(up[c][i], road_bottom))
continue;
ll nw = dp[c][i] + sm[orig] - sm[up[c][i]];
mini(ans, nw);
c = up[c][i];
}
mini(ans, (sm[orig] - sm[road_bottom]) + dpdown[road_bottom]);
if(ans >= INF) {
cout << "oo" << LINE;
}
else {
cout << ans << LINE;
}
}
void solve()
{
int n, s, q, e;
cin >> n >> s >> q >> e;
VPII edges(n - 1);
FOR(i, 0, n - 1)
{
int a, b;
ll w;
cin >> a >> b >> w;
g[a].PB({b, w});
g[b].PB({a, w});
edges[i] = {a, b};
}
in[0] = -1;
out[0] = 1e8;
FOR(i, 0, s)
{
int c;
cin >> c;
shop[c] = true;
}
dfs(e, e);
dlift(e, e);
for (auto &[a, b] : edges)
{
if (!isanc(a, b))
swap(a, b); // a must be anc of b
}
while (q--)
{
int id, c;
cin >> id >> c;
query(edges[id-1].second, c);
}
}
int main()
{
fastio();
int t = 1;
// cin >> t;
while (t--)
solve();
}
