# include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
#define pii pair <int, int>
#define pb push_back
const int N = 3e5 + 5;
int n, m, q, a[N], b[N], edge[N], par[N][20], idx[N], c[N], in[N], out[N], tin, cur;
vector <pii> v[N];
int le_[30 * N], ri_[30 * N], root[N];
pii tree[30 * N];
void dfs(int a, int p) {
par[a][0] = p;
for (int i = 1; i <= 18; i++) {
par[a][i] = par[par[a][i - 1]][i - 1];
}
in[a] = ++tin;
for (pii sth : v[a]) {
int to = sth.f, id = sth.s;
if (to == p) continue;
edge[id] = to; // {a, to}
dfs(to, a);
}
out[a] = tin;
}
int upper(int a, int b) {
return (in[a] <= in[b] && out[a] >= out[b]);
}
int lca(int a, int b) {
if (upper(a, b)) return a;
for (int i = 18; i >= 0; i--) {
if (par[a][i] && !upper(par[a][i], b)) a = par[a][i];
}
return par[a][0];
}
pii merge(pii a, pii b) {
return {a.f + b.f, a.s + b.s};
}
void build(int node, int le, int ri) {
if (le == ri) {
tree[node] = {0, 0};
return ;
}
int mid = (le + ri) / 2;
le_[node] = ++cur; ri_[node] = ++cur;
build(le_[node], le, mid);
build(ri_[node], mid + 1, ri);
tree[node] = merge(tree[le_[node]], tree[ri_[node]]);
}
void update(int node, int le, int ri, int idx, int val) {
if (le > idx || ri < idx) return ;
if (le == ri) {
tree[cur] = {tree[node].f + val, tree[node].s + ((val > 0) ? 1 : -1)};
return ;
}
int mid = (le + ri) / 2;
int x = cur;
le_[x] = le_[node]; ri_[x] = ri_[node];
if (idx <= mid) le_[x] = ++cur;
else ri_[x] = ++cur;
update(le_[node], le, mid, idx, val); // node
update(ri_[node], mid + 1, ri, idx, val); //node
tree[x] = merge(tree[le_[x]], tree[ri_[x]]);
}
pii getans(int node, int le, int ri, int start, int end) {
if (le > end || ri < start) return {0, 0};
if (le >= start && ri <= end) return tree[node];
int mid = (le + ri) / 2;
return merge(getans(le_[node], le, mid, start, end), getans(ri_[node], mid + 1, ri, start, end));
}
signed main() {
cin>>n>>m>>q;
for (int i = 1; i <= n - 1; i++) {
cin>>a[i]>>b[i];
v[a[i]].pb({b[i], i}); v[b[i]].pb({a[i], i});
}
dfs(1, 0);
vector <pii> vec;
for (int i = 1; i <= m; i++) {
cin>>idx[i]>>c[i];
idx[i] = edge[idx[i]]; // {a, to}
vec.pb({c[i], idx[i]});
}
vec.pb({0, 0});
sort(vec.begin(), vec.end());
root[0] = 1; cur = 1;
build(1, 1, n);
for (int i = 1; i < (int)vec.size(); i++) {
root[i] = ++cur;
//cout<<"update "<<in[vec[i].s]<<" "<<out[vec[i].s]<<" "<<vec[i].f<<"\n";
update(root[i - 1], 1, n, in[vec[i].s], vec[i].f);
int proot = root[i];
if (out[vec[i].s] + 1 <= n) {
root[i] = ++cur;
update(proot, 1, n, out[vec[i].s] + 1, -vec[i].f);
}
/*
for (int j = 1; j <= n; j++) {
cout<<getans(root[i], 1, n, 1, in[j]).s<<" ";
}
cout<<"\n";
*/
}
while (q--) {
int s, t, x, y;
cin>>s>>t>>x>>y; int lc = lca(s, t);
int l = 0, r = (int)vec.size() - 1, ans = -1;
while (l <= r) {
int mid = (l + r) / 2;
int silver = getans(root[mid], 1, n, 1, in[s]).f + getans(root[mid], 1, n, 1, in[t]).f - 2 * getans(root[mid], 1, n, 1, in[lc]).f;
if (silver <= y) {
ans = mid; l = mid + 1;
} else r = mid - 1;
}
if (ans == (int)vec.size() - 1) {
cout<<x<<"\n"; continue;
}
int sz = (int)vec.size() - 1;
int rem = getans(root[sz], 1, n, 1, in[s]).s + getans(root[sz], 1, n, 1, in[t]).s - 2 * getans(root[sz], 1,n, 1, in[lc]).s;
rem -= (getans(root[ans], 1, n, 1, in[s]).s + getans(root[ans], 1, n, 1, in[t]).s - 2 * getans(root[ans], 1, n, 1, in[lc]).s);
if (rem > x) cout<<-1<<"\n";
else cout<<(x - rem)<<"\n";
}
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
7380 KB |
Output is correct |
| 2 |
Correct |
4 ms |
7356 KB |
Output is correct |
| 3 |
Correct |
3 ms |
7380 KB |
Output is correct |
| 4 |
Correct |
3 ms |
7380 KB |
Output is correct |
| 5 |
Incorrect |
8 ms |
8536 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
7380 KB |
Output is correct |
| 2 |
Incorrect |
10 ms |
8648 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
7344 KB |
Output is correct |
| 2 |
Incorrect |
9 ms |
8404 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
4 ms |
7380 KB |
Output is correct |
| 2 |
Correct |
4 ms |
7356 KB |
Output is correct |
| 3 |
Correct |
3 ms |
7380 KB |
Output is correct |
| 4 |
Correct |
3 ms |
7380 KB |
Output is correct |
| 5 |
Incorrect |
8 ms |
8536 KB |
Output isn't correct |
| 6 |
Halted |
0 ms |
0 KB |
- |
