// problem B
#include <bits/stdc++.h>
using namespace std;
#define sz size()
#define pb push_back
#define ff first
#define ss second
const int N = 2e5 + 5;
int n, q, l[N], r[N], par[N], d, sub[N], sum, rt, a[N], leaf[N], leaf1[N], sub1[N];
map <int, int> m;
pair <int, int> val[N];
vector <int> v[N];
void dfs (int x, int pr) {
par[x] = pr;
for(int i : v[x]){
if(i == pr) continue;
dfs(i, x);
sub[x] += sub[i];
}
if((int)v[x].sz == 1) {
sub[x]++;
leaf[x] = 1;
}
if(~pr) {
sum += (sub[x] % 2 ? 1 : 2);
}
}
void dfs1 (int x, int pr, int bir, int iki) {
for (int i : v[x]) {
if (i == pr) continue;
int new_bir = bir, new_iki = iki;
if (sub[i] % 2) new_bir++;
else new_iki++;
val[i] = {new_bir, new_iki};
dfs1 (i, x, new_bir, new_iki);
}
}
int main () {
// freopen ("input.txt", "r", stdin);
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin >> n >> q;
for (int i = 1; i < n; ++i) {
cin >> l[i] >> r[i];
}
if ((q == 1) or (n <= 20000 and q <= 300)) {
while ( q-- ) {
for (int i = 1; i < n; ++i) {
v[l[i]].pb (r[i]);
v[r[i]].pb (l[i]);
}
for(int i = 1; i <= n; ++i){
if((int)v[i].sz > 1){
rt = i;
break;
}
}
cin >> d;
for (int i = 1; i <= d; ++i) {
cin >> a[i];
}
int san = n;
for (int i = 1; i <= d; ++i) {
san++;
v[a[i]].pb (san);
v[san].pb (a[i]);
}
sum = 0;
for (int i = 1; i <= san; ++i) sub[i] = 0;
dfs (rt, -1);
cout << (sub[rt] % 2 ? -1 : sum) << '\n';
for (int i = 1; i <= san; ++i) {
v[i].clear();
}
}
return 0;
}
for (int i = 1; i < n; ++i) {
v[l[i]].pb (r[i]);
v[r[i]].pb (l[i]);
}
for(int i = 1; i <= n; ++i){
if((int)v[i].sz > 1){
rt = i;
break;
}
}
bool subtask5 = 0;
for (int i = 1; i <= n; ++i) {
if (i == rt and (int)v[i].sz != 2) {
subtask5 = 1;
break;
}
else if (i != rt) {
if ((int)v[i].sz > 3 or (int)v[i].sz % 2 == 0) {
subtask5 = 1;
break;
}
}
}
if (!subtask5) {
dfs (rt, -1);
while ( q-- ) {
cin >> d;
m.clear();
int va = 0;
for (int i = 1; i <= d; ++i) {
cin >> a[i];
m[a[i]]++;
}
for (auto i : m) {
if (leaf[i.ff]) {
va += i.ss - 1;
}
else {
va += i.ss;
}
}
if (va % 2) {
cout << "-1\n";
continue;
}
for (int i = 1; i <= d; ++i) {
int x = a[i];
while (x != -1) {
sub1[x] = sub[x];
leaf1[x] = leaf[x];
x = par[x];
}
if (leaf[a[i]]) {
sub1[a[i]] = 0;
}
}
int sum1 = sum;
for (int i = 1; i <= d; ++i) {
int x = a[i];
sum1++;
if(!leaf1[x]) {
while (x != rt) {
if (sub1[x] % 2) {
sum1++;
sub1[x] = 2;
}
else {
sum1--;
sub1[x] = 1;
}
x = par[x];
}
}
else {
leaf1[x] = 0;
sub1[x] = 1;
}
}
cout << sum1 << "\n";
}
}
else {
dfs (rt, -1);
dfs1 (rt, -1, 0, 0);
while ( q-- ) {
cin >> d;
for (int i = 1; i <= d; ++i) {
cin >> a[i];
}
if (!(sub[rt] % 2)) {
if (leaf[a[1]]) {
cout << sum + 1 << "\n";
}
else {
cout << "-1" << "\n";
}
}
else {
// sum = -1
if (leaf[a[1]]) {
cout << "-1" << "\n";
}
else {
int jog = sum - val[a[1]].ff - (2 * val[a[1]].ss);
int jog1 = (val[a[1]].ff * 2) + val[a[1]].ss + 1;
cout << jog + jog1 << "\n";
}
}
}
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
12888 KB |
Output is correct |
2 |
Incorrect |
13 ms |
11612 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
14 ms |
15964 KB |
Output is correct |
2 |
Correct |
12 ms |
15964 KB |
Output is correct |
3 |
Correct |
20 ms |
16448 KB |
Output is correct |
4 |
Correct |
33 ms |
18132 KB |
Output is correct |
5 |
Correct |
36 ms |
19288 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
13 ms |
16476 KB |
Output is correct |
2 |
Correct |
14 ms |
16488 KB |
Output is correct |
3 |
Correct |
30 ms |
23644 KB |
Output is correct |
4 |
Correct |
45 ms |
25692 KB |
Output is correct |
5 |
Correct |
29 ms |
22588 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
224 ms |
14308 KB |
Output is correct |
2 |
Correct |
144 ms |
13724 KB |
Output is correct |
3 |
Correct |
218 ms |
13576 KB |
Output is correct |
4 |
Correct |
247 ms |
14172 KB |
Output is correct |
5 |
Correct |
206 ms |
14288 KB |
Output is correct |
6 |
Correct |
263 ms |
14160 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
31 ms |
13660 KB |
Output is correct |
2 |
Correct |
48 ms |
13400 KB |
Output is correct |
3 |
Correct |
39 ms |
12344 KB |
Output is correct |
4 |
Correct |
48 ms |
13400 KB |
Output is correct |
5 |
Correct |
49 ms |
13636 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
45 ms |
15264 KB |
Output is correct |
2 |
Correct |
45 ms |
17748 KB |
Output is correct |
3 |
Correct |
54 ms |
18056 KB |
Output is correct |
4 |
Correct |
61 ms |
17244 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
12888 KB |
Output is correct |
2 |
Incorrect |
13 ms |
11612 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |