/*
Code written by Talant I.D.
*/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
#define precision(n) fixed << setprecision(n)
#define pb push_back
#define ub upper_bound
#define lb lower_bound
#define mp make_pair
#define eps (double)1e-9
#define PI 2*acos(0.0)
#define endl "\n"
#define sz(v) int((v).size())
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define do_not_disturb ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define OK cout << "OK" << endl;
const int mod = 1e9+7;
ll mode(ll a) {
a %= mod;
if (a < 0) a += mod;
return a;
}
ll subt(ll a, ll b) {
return mode(mode(a)-mode(b));
}
ll add(ll a, ll b) {
return mode(mode(a)+mode(b));
}
ll mult(ll a, ll b) {
return mode(mode(a)*mode(b));
}
ll binpow(ll a, ll b) {
ll res = 1;
while (b) {
if (b&1) res = mult(res, a);
a = mult(a, a);
b >>= 1;
}
return res;
}
const int N = 1e5+7;
vector <int> graph[N], graph2[N];
int n, subtree[N], par[N];
bool leaf[N];
ll ans;
bool subtask1() {
return sz(graph[1]) == n-1;
}
bool subtask2() {
bool flag = 1;
for (int i = 1; i <= n; i++) {
if (i == 1) {
if (sz(graph[1]) != 1 || graph[1][0] != 2) flag = 0;
}
else if (i == n) {
if (sz(graph[n]) != 1 || graph[n][0] != n-1) flag = 0;
}
else if (sz(graph[i]) != 2 || min(graph[i][0], graph[i][1]) != i-1 || max(graph[i][0], graph[i][1]) != i+1) {
flag = 0;
}
}
return flag;
}
void dfs(int v, int p) {
par[v] = p;
subtree[v] = 0;
int children = 0;
for (auto to : graph[v]) {
if (to == p) continue;
children++;
dfs(to, v);
subtree[v] += subtree[to];
}
if (children == 0) {
subtree[v] = 1;
leaf[v] = 1;
}
if (v != p) {
if (subtree[v]&1) ans++;
else ans += 2;
}
}
void dfs2(int v, int p) {
subtree[v] = 0;
int children = 0;
for (auto to : graph2[v]) {
if (to == p) continue;
children++;
dfs2(to, v);
subtree[v] += subtree[to];
}
if (children == 0) subtree[v] = 1;
if (v != p) {
if (subtree[v]&1) ans++;
else ans += 2;
}
}
int main() {
do_not_disturb
int q;
cin >> n >> q;
for (int i = 0; i < n-1; i++) {
int x, y;
cin >> x >> y;
graph[x].pb(y);
graph[y].pb(x);
}
if (subtask1()) {
while (q--) {
int m;
cin >> m;
vector <int> d(m), has(n+1);
for (auto &to : d) cin >> to;
for (auto to : d) has[to]++;
multiset <int> st;
ll ans = 0;
for (int i = 2; i <= n; i++) {
while (has[i] > 2) {
ans += 2;
has[i] -= 2;
}
if (!has[i]) {
st.insert(1);
}
else {
while (has[i]) {
st.insert(2);
has[i]--;
}
}
}
if (sz(st)&1) {
cout << -1 << endl;
}
else {
while (sz(st)) {
auto a = *st.begin();
st.erase(st.find(a));
auto b = *st.begin();
st.erase(st.find(b));
ans += a+b;
}
cout << ans << endl;
}
}
}
else if (subtask2()) {
while (q--) {
int m;
cin >> m;
vector <int> d(m);
for (auto &to : d) cin >> to;
sort(all(d));
if (sz(d)&1) {
cout << -1 << endl;
}
else {
ll ans = n-1;
for (int i = 0; i < sz(d); i += 2) {
ans += abs(d[i]-d[i+1])+2;
}
cout << ans << endl;
}
}
}
else if (n <= 20000 && q <= 300) {
while (q--) {
ans = 0;
for (int i = 1; i <= n; i++) {
for (auto to : graph[i]) graph2[i].pb(to);
}
int nw = n;
int m;
cin >> m;
vector <int> d(m);
for (auto &to : d) cin >> to;
for (auto to : d) {
nw++;
graph2[to].pb(nw);
graph2[nw].pb(to);
}
int root = -1;
for (int i = 1; i <= nw; i++) {
if (sz(graph2[i]) != 1) {
root = i;
break;
}
}
dfs2(root, root);
if (subtree[root]%2 == 0) {
cout << ans << endl;
}
else {
cout << -1 << endl;
}
for (int i = 1; i <= nw; i++) {
graph2[i].clear();
}
}
}
else {
int root = -1;
for (int i = 1; i <= n; i++) {
if (sz(graph[i]) != 1) {
root = i;
break;
}
}
dfs(root, root);
while (q--) {
int m;
cin >> m;
ll res = ans;
vector <int> d(m);
vector <int> parity(n+1);
for (int i = 1; i <= n; i++) {
parity[i] = subtree[i]%2;
}
for (auto &to : d) cin >> to;
for (auto to : d) {
if (leaf[to]) {
res++;
}
else {
auto cur = to;
while (cur != par[cur]) {
res++;
parity[cur] = 1-parity[cur];
cur = par[cur];
}
parity[cur] = 1-parity[cur];
res++;
}
}
if (parity[root]) {
cout << -1 << endl;
}
else {
cout << res << endl;
}
}
}
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4940 KB |
Output is correct |
| 2 |
Incorrect |
187 ms |
6304 KB |
Output isn't correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
12 ms |
5580 KB |
Output is correct |
| 2 |
Correct |
12 ms |
5600 KB |
Output is correct |
| 3 |
Correct |
51 ms |
13560 KB |
Output is correct |
| 4 |
Correct |
49 ms |
12216 KB |
Output is correct |
| 5 |
Correct |
75 ms |
14776 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
18 ms |
5424 KB |
Output is correct |
| 2 |
Correct |
17 ms |
5452 KB |
Output is correct |
| 3 |
Correct |
43 ms |
8008 KB |
Output is correct |
| 4 |
Correct |
55 ms |
8132 KB |
Output is correct |
| 5 |
Correct |
40 ms |
7704 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
327 ms |
6988 KB |
Output is correct |
| 2 |
Correct |
220 ms |
6544 KB |
Output is correct |
| 3 |
Correct |
315 ms |
6348 KB |
Output is correct |
| 4 |
Correct |
346 ms |
7060 KB |
Output is correct |
| 5 |
Correct |
295 ms |
7072 KB |
Output is correct |
| 6 |
Correct |
355 ms |
7124 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1088 ms |
8204 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1090 ms |
9760 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
4940 KB |
Output is correct |
| 2 |
Incorrect |
187 ms |
6304 KB |
Output isn't correct |
