#include <bits/stdc++.h>
using namespace std;
#define sz(x) ((int)size(x))
#define all(x) begin(x), end(x)
#define trace(x) cout << #x << ": " << (x) << endl;
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l, int r) { return (int) ((ll) rnd() % (r - l + 1)) + l; }
const int N = 200000, infI = 1e9 + 7;
const ll infL = 3e18;
vector<int> g[N];
ll dp[N];//LL???
int cnt[N], parent[N], depth[N];
void pull(int v) {
dp[v] = 0;
if (sz(g[v]) <= 1) {
//v is a leaf
cnt[v] = 1;
} else {
cnt[v] = 0;
for (int to: g[v]) {
if (to != parent[v]) {
cnt[v] += cnt[to];
dp[v] += dp[to];
}
}
}
dp[v] += 2 - (cnt[v] & 1);
}
void dfs(int v, int p) {
if (p != -1) {
depth[v] = depth[p] + 1;
}
dp[v] = 0;
parent[v] = p;
if (sz(g[v]) <= 1) {
//v is a leaf
cnt[v] = 1;
} else {
cnt[v] = 0;
for (int to: g[v]) {
if (to != parent[v]) {
dfs(to, v);
cnt[v] += cnt[to];
dp[v] += dp[to];
}
}
}
dp[v] += 2 - (cnt[v] & 1);
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, q;
cin >> n >> q;
int root = -1;
for (int i = 0; i < n - 1; ++i) {
int a, b;
cin >> a >> b;
--a, --b;
g[a].push_back(b);
g[b].push_back(a);
}
int mxx = 0;
for (int i = 0; i < n; ++i) {
mxx = max(mxx, sz(g[i]));
}
for (int i = 0; i < n; ++i) {
if (sz(g[i]) > 1) {
root = i;
break;
}
}
assert(root != -1);
dfs(root, -1);
if (mxx <= 3 && *max_element(all(depth)) <= 18) {
while (q--) {
int D;
cin >> D;
vector<int> a(D);
for (int i = 0; i < D; ++i) {
cin >> a[i];
--a[i];
}
sort(all(a));
vector<int> b;
int extra = 0;
for (int i = 0; i < D;) {
int j = i;
while (j < D && a[i] == a[j])
++j;
if ((j - i) & 1) {
b.push_back(a[i]);
extra += j - i - 1;
} else {
b.push_back(a[i]);
b.push_back(a[i]);
extra += j - i - 2;
}
i = j;
}
swap(a, b);
D = sz(a);
for (int i = 0; i < D; ++i) {
g[a[i]].push_back(i + n);
}
for (int i = 0; i < D; ++i) {
pull(i + n);
if (i == D - 1 || a[i + 1] != a[i]) {
int x = a[i];
while (x != -1) {
pull(x);
x = parent[x];
}
}
}
cout << (cnt[root] % 2 == 1 ? -1 : dp[root] + extra - 2) << '\n';
for (int i = 0; i < D; ++i) {
g[a[i]].pop_back();
if (i == D - 1 || a[i + 1] != a[i]) {
int x = a[i];
while (x != -1) {
pull(x);
x = parent[x];
}
}
}
}
} else {
while (q--) {
int D;
cin >> D;
vector<int> a(D);
for (int i = 0; i < D; ++i) {
cin >> a[i];
--a[i];
}
for (int i = 0; i < D; ++i) {
g[a[i]].push_back(i + n);
}
dfs(root, -1);
cout << (cnt[root] % 2 == 1 ? -1 : dp[root] - 2) << '\n';
for (int i = 0; i < D; ++i) {
g[a[i]].pop_back();
}
}
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4948 KB |
Output is correct |
2 |
Execution timed out |
1089 ms |
6764 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
15 ms |
7968 KB |
Output is correct |
2 |
Correct |
22 ms |
7972 KB |
Output is correct |
3 |
Correct |
34 ms |
11324 KB |
Output is correct |
4 |
Correct |
44 ms |
12084 KB |
Output is correct |
5 |
Correct |
55 ms |
13976 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
8532 KB |
Output is correct |
2 |
Correct |
17 ms |
8652 KB |
Output is correct |
3 |
Correct |
74 ms |
18956 KB |
Output is correct |
4 |
Correct |
74 ms |
20560 KB |
Output is correct |
5 |
Correct |
46 ms |
17664 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
223 ms |
7412 KB |
Output is correct |
2 |
Correct |
163 ms |
6608 KB |
Output is correct |
3 |
Correct |
200 ms |
6184 KB |
Output is correct |
4 |
Correct |
263 ms |
6876 KB |
Output is correct |
5 |
Correct |
230 ms |
7016 KB |
Output is correct |
6 |
Correct |
247 ms |
7108 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
93 ms |
9816 KB |
Output is correct |
2 |
Correct |
108 ms |
9932 KB |
Output is correct |
3 |
Correct |
85 ms |
7788 KB |
Output is correct |
4 |
Correct |
113 ms |
9892 KB |
Output is correct |
5 |
Correct |
127 ms |
9920 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1074 ms |
11324 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4948 KB |
Output is correct |
2 |
Execution timed out |
1089 ms |
6764 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |