#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int, int>
#define ff first
#define ss second
#define pb push_back
// global
// persistent segment tree (point add range sum)
struct Node {
int val, cnt;
Node *l, *r;
Node() : val(0), cnt(0), l(nullptr), r(nullptr) {}
Node(int x, int y) : val(x), cnt(y), l(nullptr), r(nullptr) {}
Node(Node *ll, Node *rr) : val(ll->val + rr->val), cnt(ll->cnt + rr->cnt), l(ll), r(rr) {}
};
const int mxN = 1e5 + 1;
int n;
Node *segstore[mxN];
Node *SegBuild(int l = 1, int r = n) {
if (l == r) {
return new Node();
}
int mid = (l + r) >> 1;
return new Node(SegBuild(l, mid), SegBuild(mid + 1, r));
}
Node *SegUpdate(Node *seg, int pos, int val, int l = 1, int r = n) {
if (l == r) {
return new Node(seg->val + val, seg->cnt + 1);
}
int mid = (l + r) >> 1;
if (pos <= mid) {
return new Node(SegUpdate(seg->l, pos, val, l, mid), seg->r);
} else {
return new Node(seg->l, SegUpdate(seg->r, pos, val, mid + 1, r));
}
return new Node();
}
pii SegQuery(Node *seg, int &tl, int &tr, int l = 1, int r = n) {
if (tl <= l && r <= tr) {
return {seg->val, seg->cnt};
}
int mid = (l + r) >> 1;
pii res = {0, 0};
pii ret;
if (tl <= mid) {
ret = SegQuery(seg->l, tl, tr, l, mid);
res.ff += ret.ff; res.ss += ret.ss;
}
if (tr > mid) {
ret = SegQuery(seg->r, tl, tr, mid + 1, r);
res.ff += ret.ff; res.ss += ret.ss;
}
return res;
}
// hld
vector<int> adj[mxN];
int par[mxN], rr[mxN], sz[mxN];
int heavy[mxN]; // heavy edge for children
int root[mxN]; // root of heavy edges
int corr[mxN]; // euler tour to map to segtree
void HLDInit(int u = 1, int pp = 0) {
par[u] = pp;
rr[u] = rr[pp] + 1;
sz[u] = 1;
pii big = {-1, -1};
for (int v : adj[u]) {
if (v != pp) {
HLDInit(v, u);
sz[u] += sz[v];
if (sz[v] > big.ff) big = {sz[v], v};
}
}
heavy[u] = big.ss;
}
int segptr = 1;
void HLDProcess(int u = 1, int pp = 0, int high = 1) {
root[u] = high;
corr[u] = segptr++;
if (heavy[u] == -1) return;
HLDProcess(heavy[u], u, high);
for (int v : adj[u]) {
if (v != heavy[u] && v != pp) HLDProcess(v, u, v);
}
}
int HLDLCA(int u, int v) {
while (root[u] != root[v]) {
if (rr[root[u]] > rr[root[v]]) swap(u, v);
v = par[root[v]];
}
return (rr[u] < rr[v] ? u : v);
}
void HLDUpdate(int &ver, int u, int v, int &val) {
// depth[u] < depth[v], update v
if (rr[u] > rr[v]) swap(u, v);
// cerr << "HLDUPDATE " << u << ' ' << v << endl;
segstore[ver] = SegUpdate(segstore[ver - 1], corr[v], val);
}
pii HLDQueryAnces(int &ver, int u, int v) {
int ptr1, ptr2;
pii res = {0, 0};
pii ret;
while (root[u] != root[v]) {
ptr1 = corr[u]; ptr2 = corr[root[u]];
if (ptr1 > ptr2) swap(ptr1, ptr2);
ret = SegQuery(segstore[ver], ptr1, ptr2);
res.ff += ret.ff; res.ss += ret.ss;
u = par[root[u]];
}
if (rr[u] > rr[v]) swap(u, v);
if (u != v) {
ptr1 = corr[heavy[u]]; ptr2 = corr[v];
if (ptr1 > ptr2) swap(ptr1, ptr2);
ret = SegQuery(segstore[ver], ptr1, ptr2);
res.ff += ret.ff; res.ss += ret.ss;
}
return res;
}
pii HLDQuery(int &ver, int u, int v) {
int lca = HLDLCA(u, v);
pii lhs = HLDQueryAnces(ver, u, lca);
pii rhs = HLDQueryAnces(ver, v, lca);
// cerr << "HLDQUERY\n";
// cerr << ver << ' ' << u << ' ' << v << ' ' << lca << endl;
// cerr << lhs.ff << ' ' << lhs.ss << endl;
// cerr << rhs.ff << ' ' << rhs.ss << endl;
return {lhs.ff + rhs.ff, lhs.ss + rhs.ss};
}
void init() {
// init
}
void solve() {
// solve
int m, q;
cin >> n >> m >> q;
pii edges[n];
for (int i = 1; i <= n - 1; i++) {
int u, v;
cin >> u >> v;
adj[u].pb(v);
adj[v].pb(u);
edges[i] = {u, v};
}
HLDInit();
HLDProcess();
pii updates[m + 1];
for (int i = 1; i <= m; i++) {
cin >> updates[i].ff >> updates[i].ss;
}
sort(updates + 1, updates + m + 1, [&](pii &lhs, pii &rhs) { return lhs.ss < rhs.ss; });
segstore[0] = SegBuild();
for (int i = 1; i <= m; i++) {
HLDUpdate(i, edges[updates[i].ff].ff, edges[updates[i].ff].ss, updates[i].ss);
}
while (q--) {
int s, t, x, y;
cin >> s >> t >> x >> y;
int lb = 0, rb = m;
pii ret;
while (lb < rb) {
int mid = (lb + rb + 1) >> 1;
ret = HLDQuery(mid, s, t);
if (ret.ff <= y) {
lb = mid;
} else {
rb = mid - 1;
}
}
ret = HLDQuery(lb, s, t);
// cerr << lb << ' ' << ret.ff << ' ' << ret.ss << endl;
// cerr << HLDQuery(m, s, t).ff << ' ' << HLDQuery(m, s, t).ss << endl;
x -= HLDQuery(m, s, t).ss - HLDQuery(lb, s, t).ss;
cout << (x < 0 ? -1 : x) << '\n';
}
}
int32_t main() {
ios::sync_with_stdio(0); cin.tie(0);
init(); solve();
}
