#include <bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define FOR(i, a, b) for (int i = a, _b = b; i <= _b; ++i)
#define FORD(i, a, b) for (int i = a, _b = b; i >= _b; --i)
#define FORLL(i, a, b) for (ll i = a, _b = b; i <= _b; ++i)
#define FORDLL(i, a, b) for (ll i = a, _b = b; i >= _b; --i)
#define all(x) x.begin(), x.end()
#define uni(x) sort(all(x)), x.erase(unique(all(x)), x.end())
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define dbg(...) debug(#__VA_ARGS__, __VA_ARGS__)
template<typename T>
void __print_one(const char *&s, const T &x)
{
while (*s == ' ') ++s;
const char *p = s;
int bal = 0;
while (*s)
{
if (*s == '(') ++bal;
else if (*s == ')') --bal;
else if (*s == ',' && bal == 0) break;
++s;
}
cerr.write(p, s - p) << " = " << x;
if (*s == ',')
{
++s;
cerr << " , ";
}
}
template<typename... Args>
void debug(const char *s, Args... args)
{
cerr << "[ ";
int dummy[] = { 0 , ( __print_one(s, args) , 0 )... };
(void)dummy;
cerr << " ]\n\n";
}
template<class X>
bool maximize(X &a, X b)
{
if (a < b)
{
a = b;
return true;
}
return false;
}
template<class X>
bool minimize(X &a, X b)
{
if (a > b)
{
a = b;
return true;
}
return false;
}
// --------------------------------------------------------------------------------------------
const int maxn = 1e5 + 3;
int n, S, q, E;
vector<pii> g[maxn];
pii Eds[maxn];
bitset<maxn> has;
// --------------------------------------------------------------------------------------------
namespace AC
{
int tin[maxn], tout[maxn], tdfs, hv[maxn], sz[maxn], par[maxn], nx[maxn][20], head[maxn];
ll dp_down[maxn], dp_up[maxn], vals[maxn], D[maxn];
vector<ll> PRE[maxn], SUFF[maxn];
vector<pii> NODES[maxn];
ll Nhay[maxn][20], NhayUp[maxn][20];
void dfs_down(int u, int p)
{
tin[u] = ++tdfs;
sz[u] = 1;
if (has[u])
dp_down[u] = 0;
for (const auto &e : g[u])
{
if (e.fi == p) continue;
par[e.fi] = u;
vals[e.fi] = e.se;
D[e.fi] = D[u] + e.se;
dfs_down(e.fi, u);
sz[u] += sz[e.fi];
if (sz[e.fi] > sz[hv[u]])
hv[u] = e.fi;
NODES[u].push_back(e);
minimize(dp_down[u], dp_down[e.fi] + e.se);
}
PRE[u].assign(int(NODES[u].size()) + 3, ll(1e18));
SUFF[u].assign(int(NODES[u].size()) + 3, ll(1e18));
FOR(id, 0, int(NODES[u].size()) - 1)
{
auto &e = NODES[u][id];
PRE[u][id] = dp_down[e.fi] + e.se;
if (id)
minimize(PRE[u][id], PRE[u][id - 1]);
}
FORD(id, int(NODES[u].size()) - 1, 0)
{
auto &e = NODES[u][id];
SUFF[u][id] = dp_down[e.fi] + e.se;
if (id < int(NODES[u].size()) - 1)
minimize(SUFF[u][id], SUFF[u][id + 1]);
}
tout[u] = tdfs;
}
void dfs_up(int u, int p)
{
FOR(id, 0, int(NODES[u].size()) - 1)
{
auto &e = NODES[u][id];
ll cur = has[u] ? 0 : ll(1e18);
if (id) minimize(cur, PRE[u][id - 1]);
minimize(cur, SUFF[u][id + 1]);
minimize(cur, dp_up[u] + vals[u]);
}
for (const auto &e : NODES[u])
dfs_up(e.fi, u);
}
int root = 1;
void hld(int u)
{
head[u] = root;
tin[u] = ++tdfs;
if (hv[u])
{
hld(hv[u]);
for (const auto &e : NODES[u])
{
root = e.fi;
hld(e.fi);
}
}
tout[u] = tdfs;
}
bool onPath(int u, int v, int k)
{
while (head[u] != head[v])
{
if (tin[u] < tin[v]) swap(u, v);
if (tin[k] >= tin[head[u]] && tin[k] <= tin[u]) return true;
u = par[head[u]];
}
if (tin[u] > tin[v]) swap(u, v);
return tin[k] >= tin[u] && tin[k] <= tin[v];
}
void solve()
{
vals[1] = ll(1e18);
FOR(i, 1, n)
{
dp_down[i] = ll(1e18);
dp_up[i] = ll(1e18);
}
dfs_down(1, -1);
dfs_up(1, -1);
hld(1);
FOR(i, 1, n)
{
nx[i][0] = par[i];
Nhay[i][0] = -D[i] + dp_down[i];
NhayUp[i][0] = D[par[i]] + dp_up[i];
}
FOR(j, 1, 19)
{
FOR(i, 1, n)
{
nx[i][j] = nx[nx[i][j - 1]][j - 1];
Nhay[i][j] = min(Nhay[i][j - 1], Nhay[nx[i][j - 1]][j - 1]);
NhayUp[i][j] = min(NhayUp[i][j - 1], NhayUp[nx[i][j - 1]][j - 1]);
}
}
while (q--)
{
int Canh, Dinh; cin >> Canh >> Dinh;
int u = Eds[Canh].fi, v = Eds[Canh].se;
if (tin[u] > tin[v]) swap(u, v);
if (!onPath(Dinh, E, u) || !onPath(Dinh, E, v))
{
cout << "escaped\n";
continue;
}
ll res = 1e18;
ll them = 0;
if (!(tin[Dinh] <= tin[u] && tout[Dinh] >= tin[u]))
{
int org = Dinh;
for (int i = 19; i >= 0; --i)
{
if (nx[Dinh][i] == 0) continue;
int bruh = nx[Dinh][i];
if (tin[bruh] <= tin[u] && tout[bruh] >= tin[u]) continue;
minimize(res, D[org] + Nhay[Dinh][i]);
them += D[Dinh] - D[bruh];
Dinh = nx[Dinh][i];
}
minimize(res, D[org] + Nhay[Dinh][0]);
them += vals[Dinh];
Dinh = par[Dinh];
}
if (!(tin[Dinh] >= tin[v] && tin[Dinh] <= tout[v]))
{
int org = v;
FORD(i, 19, 0)
{
if (nx[v][i] == 0) continue;
int bruh = nx[u][i];
if (tin[Dinh] >= tin[bruh] && tin[Dinh] <= tout[bruh]) continue;
minimize(res, them + NhayUp[v][i] - D[Dinh]);
}
minimize(res, them + NhayUp[v][0] - D[Dinh]);
v = par[v];
them += D[u] - D[Dinh];
Dinh = u;
v = org;
FOR(id, 0, int(NODES[u].size()) - 1)
{
auto &e = NODES[u][id];
if (e.fi == v)
{
ll cur = has[u] ? 0 : ll(1e18);
if (id) minimize(cur, PRE[u][id - 1]);
minimize(cur, SUFF[u][id + 1]);
minimize(res, cur + them);
break;
}
}
}
cout << res << '\n';
}
}
}
void solve()
{
cin >> n >> S >> q >> E;
FOR(i, 2, n)
{
int u, v, w; cin >> u >> v >> w;
if (u > v) swap(u, v);
g[u].push_back({v, w});
g[v].push_back({u, w});
Eds[i - 1] = {u, v};
}
FOR(i, 1, S)
{
int x; cin >> x;
has[x] = 1;
}
AC :: solve();
}
signed main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define TASK "TEST"
if (fopen(TASK".INP", "r"))
{
freopen(TASK".INP", "r", stdin);
freopen(TASK".OUT", "w", stdout);
}
solve();
return 0;
}
