#include <bits/stdc++.h>
using namespace std;
class SplayTree {
public:
struct Node {
int ch[2] = {0, 0}, p = 0;
int val = 0;
Node(int v = 0) : val(v) {}
};
vector<Node> T;
SplayTree(int n) : T(n + 1) {}
void Push(int x) {
}
void Pull(int x) {
Push(T[x].ch[0]), Push(T[x].ch[1]);
}
void Set(int p, int d, int u) {
T[p].ch[d] = u; T[u].p = p; Pull(p);
}
int Dir(int x) {
if (!x || !T[x].p) return -1;
return T[T[x].p].ch[0] == x ? 0 : T[T[x].p].ch[1] == x ? 1 : -1;
}
void Rot(int x) {
int y = T[x].p, z = T[y].p;
int dx = Dir(x), dy = Dir(y);
Set(y, dx, T[x].ch[!dx]);
Set(x, !dx, y);
if (~dy) Set(z, dy, x);
T[x].p = z;
}
void Splay(int x) {
for (Push(x); ~Dir(x);) {
int y = T[x].p, z = T[y].p;
Push(z), Push(y), Push(x);
int dx = Dir(x), dy = Dir(y);
if (~dy) Rot(dx == dy ? y : x);
Rot(x);
}
}
};
class LinkCut : public SplayTree {
public:
LinkCut(int n) : SplayTree(n) {}
void Access(int x) {
for (int u = x, prv = 0; u; u = T[u].p) {
Splay(u);
Set(u, 1, prv);
prv = u;
}
Splay(x);
}
void Link(int par, int ch) {
Access(par), Access(ch), Set(par, 1, ch);
}
void Cut(int x) {
Access(x);
if (T[x].ch[0]) {
T[T[x].ch[0]].p = 0;
T[x].ch[0] = 0;
Pull(x);
}
}
int Root(int x) {
Access(x);
while (T[x].ch[0]) x = T[x].ch[0];
Access(x);
return T[x].val;
}
};
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int N, M, Q;
scanf("%d %d %d", &N, &M, &Q);
vector<vector<int>> adj(N + 1);
vector<pair<int, int>> edge(N);
for (int i = 1; i < N; i++) {
int x, y;
scanf("%d %d", &x, &y);
edge[i] = {x, y};
adj[x].emplace_back(y);
adj[y].emplace_back(x);
}
vector<int> depth(N + 1);
const auto Dfs = [&](const auto &self, int u, int p) -> void {
for (auto v : adj[u]) if (v != p) {
depth[v] = depth[u] + 1;
self(self, v, u);
}
};
Dfs(Dfs, 1, 0);
vector<int> ans(N + 1, 1);
vector<int> last(N, 0);
vector<int> state(N, 0);
LinkCut lct(N);
for (int i = 1; i <= N; i++) {
lct.T[i].val = i;
}
while (M--) {
int e;
scanf("%d", &e);
auto [x, y] = edge[e];
if (depth[x] > depth[y]) swap(x, y);
state[e] ^= 1;
if (state[e] == 0) { // delete edge
int t = ans[lct.Root(x)];
lct.Cut(y);
last[e] = ans[lct.Root(x)] = ans[lct.Root(y)] = t;
} else { // add edge
ans[lct.Root(x)] = ans[lct.Root(x)] + ans[lct.Root(y)] - last[e];
lct.Link(x, y);
}
}
while (Q--) {
int u;
scanf("%d", &u);
printf("%d\n", ans[lct.Root(y)]);
}
return 0;
}
Compilation message
synchronization.cpp: In function 'int main()':
synchronization.cpp:140:33: error: 'y' was not declared in this scope
140 | printf("%d\n", ans[lct.Root(y)]);
| ^
synchronization.cpp:91:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
91 | scanf("%d %d %d", &N, &M, &Q);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
synchronization.cpp:97:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
97 | scanf("%d %d", &x, &y);
| ~~~~~^~~~~~~~~~~~~~~~~
synchronization.cpp:123:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
123 | scanf("%d", &e);
| ~~~~~^~~~~~~~~~
synchronization.cpp:139:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
139 | scanf("%d", &u);
| ~~~~~^~~~~~~~~~
