#include <bits/stdc++.h>
using namespace std;
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, m, t, l;
cin >> n >> m >> t >> l;
vector<vector<pair<int, int>>> g(n);
for (int i = 0; i < m; i++) {
int x, y, z;
cin >> x >> y >> z;
--x; --y;
g[x].emplace_back(y, z);
g[y].emplace_back(x, z);
}
vector<int> seq(l);
for (int i = 0; i < l; i++) {
cin >> seq[i];
--seq[i];
}
vector<int> deg(n);
for (int i = 0; i < n; i++) {
deg[i] = (int) g[i].size();
}
vector<vector<int>> idx(n, vector<int>(n));
for (int i = 0; i < n; i++) {
for (int j = 0; j < deg[i]; j++) {
idx[i][g[i][j].first] = j;
}
}
const long long inf = (long long) 1e18;
vector<vector<vector<vector<long long>>>> dist(n, vector<vector<vector<long long>>>(n));
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
if (i == j) {
continue;
}
dist[i][j].resize(deg[i]);
for (int k = 0; k < deg[i]; k++) {
dist[i][j][k] = vector<long long>(deg[j], inf);
}
}
}
vector<vector<long long>> d(n);
for (int i = 0; i < n; i++) {
d[i].resize(deg[i]);
}
vector<int> ia(n), ib(n);
set<tuple<long long, int, int>> que;
for (int ver = 0; ver < n; ver++) {
for (int e = 0; e < deg[ver]; e++) {
for (int i = 0; i < n; i++) {
for (int j = 0; j < deg[i]; j++) {
d[i][j] = inf;
}
ia[i] = -1;
ib[i] = -1;
}
int to = g[ver][e].first;
int w = g[ver][e].second;
d[to][idx[to][ver]] = w;
que.clear();
que.emplace(d[to][idx[to][ver]], to, idx[to][ver]);
ia[to] = idx[to][ver];
auto Update = [&](int x, int y, long long z) {
if (ia[x] == y || ib[x] == y) {
que.erase(que.find({d[x][y], x, y}));
}
d[x][y] = z;
if (ia[x] == y) {
return;
}
if (ib[x] == y) {
if (d[x][y] < d[x][ia[x]]) {
swap(ia[x], ib[x]);
}
return;
}
if (ia[x] == -1) {
ia[x] = y;
que.emplace(d[x][y], x, y);
return;
}
if (ib[x] == -1) {
if (d[x][y] < d[x][ia[x]]) {
swap(ia[x], ib[x]);
ia[x] = y;
} else {
ib[x] = y;
}
que.emplace(d[x][y], x, y);
return;
}
if (d[x][y] >= d[x][ia[x]] && d[x][y] < d[x][ib[x]]) {
que.erase(que.find({d[x][ib[x]], x, ib[x]}));
ib[x] = y;
que.emplace(d[x][y], x, y);
return;
}
if (d[x][y] < d[x][ia[x]]) {
que.erase(que.find({d[x][ib[x]], x, ib[x]}));
swap(ia[x], ib[x]);
ia[x] = y;
que.emplace(d[x][y], x, y);
}
};
while (!que.empty()) {
auto it = que.begin();
int v = get<1>(*it);
int lst = get<2>(*it);
que.erase(it);
for (int i = 0; i < deg[v]; i++) {
if (i == lst) {
continue;
}
int to = g[v][i].first;
int w = g[v][i].second;
if (d[to][idx[to][v]] > d[v][lst] + w) {
Update(to, idx[to][v], d[v][lst] + w);
assert((int) que.size() <= 2 * n);
}
}
}
for (int i = ver + 1; i < n; i++) {
if (i == ver) {
continue;
}
for (int j = 0; j < deg[i]; j++) {
dist[ver][i][e][j] = d[i][j];
}
}
}
}
vector<vector<vector<vector<int>>>> good(n, vector<vector<vector<int>>>(n, vector<vector<int>>(2)));
vector<vector<int>> cc(n, vector<int>(2));
for (int from = 0; from < n; from++) {
for (int to = 0; to < n; to++) {
if (from == to) {
continue;
}
vector<pair<int, int>> order;
for (int i = 0; i < deg[from]; i++) {
for (int j = 0; j < deg[to]; j++) {
order.emplace_back(i, j);
}
}
if (from <= to) {
sort(order.begin(), order.end(), [&](pair<int, int> a, pair<int, int> b) {
return dist[from][to][a.first][a.second] < dist[from][to][b.first][b.second];
});
} else {
sort(order.begin(), order.end(), [&](pair<int, int> a, pair<int, int> b) {
return dist[to][from][a.second][a.first] < dist[to][from][b.second][b.first];
});
}
int total = 0;
for (auto& p : order) {
if (cc[p.first][0] >= 2 || cc[p.second][1] >= 2) {
continue;
}
good[from][to][0].push_back(p.first);
good[from][to][1].push_back(p.second);
cc[p.first][0] += 1;
cc[p.second][1] += 1;
total += 1;
if (total >= 5) {
break;
}
}
for (int i = 0; i < deg[from]; i++) {
cc[i][0] = 0;
}
for (int i = 0; i < deg[to]; i++) {
cc[i][1] = 0;
}
}
}
vector<vector<int>> f(l);
for (int i = 0; i < l; i++) {
if (i > 0) {
for (int j : good[seq[i - 1]][seq[i]][1]) {
f[i].push_back(j);
}
}
if (i + 1 < l) {
for (int j : good[seq[i]][seq[i + 1]][0]) {
f[i].push_back(j);
}
}
sort(f[i].begin(), f[i].end());
f[i].erase(unique(f[i].begin(), f[i].end()), f[i].end());
}
auto Update = [&](int i) {
f[i].clear();
if (i > 0) {
for (int j : good[seq[i - 1]][seq[i]][1]) {
f[i].push_back(j);
}
}
if (i + 1 < l) {
for (int j : good[seq[i]][seq[i + 1]][0]) {
f[i].push_back(j);
}
}
sort(f[i].begin(), f[i].end());
f[i].erase(unique(f[i].begin(), f[i].end()), f[i].end());
};
vector<vector<vector<long long>>> st(4 * l);
auto Pull = [&](int x) {
st[x].clear();
for (int ll = 0; ll < (int) st[x * 2].size(); ll++) {
for (int lr = 0; lr < (int) st[x * 2][ll].size(); lr++) {
if (st[x].empty()) {
st[x].resize((int) st[x * 2].size());
}
for (int rl = 0; rl < (int) st[x * 2 + 1].size(); rl++) {
if (st[x][ll].empty()) {
st[x][ll] = vector<long long>((int) st[x * 2 + 1][rl].size(), inf);
}
if (lr == rl) {
continue;
}
for (int rr = 0; rr < (int) st[x * 2 + 1][rl].size(); rr++) {
st[x][ll][rr] = min(st[x][ll][rr], st[x * 2][ll][lr] + st[x * 2 + 1][rl][rr]);
}
}
}
}
};
function<void(int, int, int)> Build = [&](int x, int l, int r) {
if (l == r) {
st[x].resize(f[l].size());
for (int i = 0; i < f[l].size(); i++) {
st[x][i] = vector<long long>(f[l + 1].size(), inf);
}
for (int i = 0; i < f[l].size(); i++) {
for (int j = 0; j < f[l + 1].size(); j++) {
if (seq[l] <= seq[l + 1]) {
st[x][i][j] = min(st[x][i][j], dist[seq[l]][seq[l + 1]][f[l][i]][f[l + 1][j]]);
} else {
st[x][i][j] = min(st[x][i][j], dist[seq[l + 1]][seq[l]][f[l + 1][j]][f[l][i]]);
}
}
}
return;
}
int mid = l + r >> 1;
Build(x * 2, l, mid);
Build(x * 2 + 1, mid + 1, r);
Pull(x);
};
function<void(int, int, int, int)> Modify = [&](int x, int l, int r, int p) {
if (l == r) {
st[x].clear();
st[x].resize(f[l].size());
for (int i = 0; i < f[l].size(); i++) {
st[x][i] = vector<long long>(f[l + 1].size(), inf);
}
for (int i = 0; i < f[l].size(); i++) {
for (int j = 0; j < f[l + 1].size(); j++) {
if (seq[l] <= seq[l + 1]) {
st[x][i][j] = min(st[x][i][j], dist[seq[l]][seq[l + 1]][f[l][i]][f[l + 1][j]]);
} else {
st[x][i][j] = min(st[x][i][j], dist[seq[l + 1]][seq[l]][f[l + 1][j]][f[l][i]]);
}
}
}
return;
}
int mid = l + r >> 1;
if (p <= mid) {
Modify(x * 2, l, mid, p);
} else {
Modify(x * 2 + 1, mid + 1, r, p);
}
Pull(x);
};
for (int i = 0; i < l; i++) {
Update(i);
}
Build(1, 0, l - 2);
auto Solve = [&]() {
long long res = inf;
for (int i = 0; i < st[1].size(); i++) {
for (int j = 0; j < st[1][i].size(); j++) {
res = min(res, st[1][i][j]);
}
}
return (res == inf ? -1LL : res);
};
while (t--) {
int p, x;
cin >> p >> x;
--p; --x;
seq[p] = x;
Update(p);
if (p > 0) {
Update(p - 1);
}
if (p + 1 < l) {
Update(p + 1);
}
if (p <= l - 2) {
Modify(1, 0, l - 2, p);
}
if (p + 1 <= l - 2) {
Modify(1, 0, l - 2, p + 1);
}
if (p + 2 <= l - 2) {
Modify(1, 0, l - 2, p + 2);
}
if (p > 0) {
Modify(1, 0, l - 2, p - 1);
}
if (p > 1) {
Modify(1, 0, l - 2, p - 2);
}
cout << Solve() << '\n';
}
return 0;
}
