#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#define endl '\n'
#define db double
#define ll __int128
#define int long long
#define pb push_back
#define fs first
#define sd second
#define Mod long(1e9 + 7)
#define all(x) x.begin(), x.end()
#define unvisited long(-1)
#define Eps double(1e-9)
#define _for(i, n) for(int i = 0; i < (n); i++)
#define dbg(x) cout << #x ": " << x << endl;
const int Max = 1e6 + 7, Inf = 1e9 + 7;
void print(bool x) { cout << (x ? "YES" : "NO") << endl; }
string tostring (__int128 x)
{
string ans = "";
while(x > 0)
{
ans += (x % 10 + '0');
x /= 10;
}
reverse(all(ans));
return ans;
}
struct LowerCommonAncestor
{
vector <vector<int>> v;
vector <int> L, E, H, lg; int idx, n;
void dfs(int cur, int depth, int parent)
{
H[cur] = idx;
E[idx] = cur;
L[idx++] = depth;
for (auto& u : v[cur]) if(u != parent)
{
dfs(u, depth + 1, cur);
E[idx] = cur;
L[idx++] = depth;
}
}
vector <vector<int>> Spt;
void RMQ()
{
Spt.assign(2 * n, vector <int>(log2(2 * n) + 1, 0));
for (int i = 0; i < 2 * n; i++)
Spt[i][0] = i;
for (int j = 1; (1 << j) <= 2 * n; j++)
{
for (int i = 0; i + (1 << j) < 2 * n; i++)
if (L[Spt[i][j - 1]] < L[Spt[i + (1 << (j - 1))][j - 1]])
Spt[i][j] = Spt[i][j - 1];
else
Spt[i][j] = Spt[i + (1 << (j - 1))][j - 1];
}
}
int Query(int i, int j)
{
if(i > j) swap(i, j);
int k = (int) lg[j-i+1];
if (L[Spt[i][k]] <= L[Spt[j - (1 << k) + 1][k]])
return Spt[i][k];
else
return Spt[j - (1 << k) + 1][k];
}
int Ancestor(int i, int j)
{
int a = min(H[i], H[j]), b = max(H[i], H[j]);
return E[Query(a, b)];
}
LowerCommonAncestor(vector<vector<int>> &p, int lenght, int x)
{
n = lenght; idx = 1; v = p;
L.assign(2 * n, -1);
E.assign(2 * n, -1);
H.assign(2 * n, -1);
lg.assign(2*n+1, 0);
_for(i, 2*n+1){
lg[i] = floor(log((double) i) / log(2.0));
}
dfs(x, 0, 0); RMQ();
}
};
int sqrt_n;
struct SegmentTreeSum
{
struct node
{
int val, cnt;
node(int v = 0, int t = 0)
{
val = v; cnt = t;
}
};
vector <node> tree; int l;
node merge(node a, node b)
{
return node(a.val + b.val, a.cnt + b.cnt);
}
void update(int k, int v)
{
k += (l - 1) + 1; tree[k] = node(v, (v != 0));
for(k /= 2; k > 0; k /= 2)
tree[k] = merge(tree[2*k], tree[2*k+1]);
}
node query(int k, int x, int y, int s, int e)
{
if(s > y || e < x)
return node();
if(s >= x && e <= y)
return tree[k];
int middle = (s + e) / 2;
return merge(query(2*k, x, y, s, middle),
query(2*k+1, x, y, middle + 1, e));
}
pair <int, int> query(int x, int y)
{
if(x > y) return { 0, 0 };
node ans = query(1, x+1, y+1, 1, l);
return { ans.val, ans.cnt };
}
SegmentTreeSum(int n)
{
for(l = 1; l < n; (l <<= 1));
tree.assign(2 * l, node());
}
};
struct query
{
int l, r, s, t, x, y, id;
bool operator < (const query &a) const {
if(long(a.l/sqrt_n) == long(l/sqrt_n))
return (long(a.l/sqrt_n) < long(l/sqrt_n));
return a.r < r;
}
query(int a, int b, int c, int d, int f, int g, int i){
l = a; r = b; s = c; t = d; x = f; y = g; id = i;
}
};
vector <int> cmp(vector <int> &s)
{
vector <pair<int, int>> t;
vector <int> ans(s.size());
_for(i, s.size()){
t.push_back({ s[i], i });
}
sort(all(t));
_for(i, s.size()){
ans[t[i].sd] = i;
}
return ans;
}
void solve()
{
int n, m, q; cin >> n >> m >> q;
sqrt_n = sqrt(n) + 1;
vector <vector<int>> v(n+1, vector <int> ()),
e(n+1, vector <int> ());
vector <int> f1(n+1), f2(n+1), s, cost(m);
vector <pair<int, int>> edge;
_for(i, n-1)
{
int a, b; cin >> a >> b;
v[a].pb(b); v[b].pb(a);
edge.push_back({ a, b });
}
function <void(int, int)> dfs = [&](int node, int parent){
f1[node] = s.size();
s.push_back(node);
for(auto& u : v[node]) if(u != parent){
dfs(u, node);
}
f2[node] = s.size();
s.push_back(node);
}; dfs(1, 0);
_for(i, m)
{
int p; cin >> p >> cost[i]; p--;
if(f1[edge[p].fs] > f1[edge[p].sd])
p = edge[p].fs;
else
p = edge[p].sd;
//cerr << p << " " << cost[i] << endl;
e[p].push_back(i);
}
vector <int> freq(n+1), pos = cmp(cost), ans(q);
vector <query> c; LowerCommonAncestor Lc(v, n, 1);
//for(auto& u : s) cerr << u << " "; cerr << endl;
_for(i, q)
{
int a, b, x, y; cin >> a >> b >> x >> y;
if(f1[a] > f1[b]) swap(a, b);
int lca = Lc.Ancestor(a, b);
c.push_back(query((a == lca ? f1[a]+1 : f2[a]), f1[b], a, b, x, y, i));
}
int l = 0, r = -1, sum = 0; sort(all(c));
SegmentTreeSum St(m+3);
auto add = [&](int x){
freq[x] = (freq[x] + 1) % 2;
for(auto& u : e[x])
{
if(freq[x] == 0){
St.update(pos[u], 0);
sum--;
}else {
St.update(pos[u], cost[u]);
sum++;
}
}
};
_for(i, q)
{
if(c[i].l > c[i].r){
cout << "WA" << endl;
break;
}
while (r < c[i].r){
r++; //cerr << i<< " " << r << " " << s[r] << " " << c[i].r << endl;
add(s[r]);
}
while (l > c[i].l){
l--;
add(s[l]);
}
while (r > c[i].r){
add(s[r]);
r--;
}
while (l < c[i].l){
add(s[l]);
l++;
}
// cerr << "pas" << endl;
//continue;
//cerr << c[i].s << " " << c[i].t << " " << lca << " " << sum << endl;
int a = -1, b = m+2;
while (abs(a - b) != 1)
{
int mid = (a + b) / 2;
if(St.query(0, mid).fs <= c[i].y)
a = mid;
else
b = mid;
}
pair <int, int> sx = St.query(0, a); //cerr << c[i].l << " " << c[i].r << " " << sum << " " << sx.fs << endl;
ans[c[i].id] = max(-1LL, c[i].x - (sum - sx.sd));
}
for(auto& u : ans) cout << u << endl;
}
int32_t main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int Q = 1; //cin >> Q;
while (Q--)
{
solve();
}
return 0;
}
