#include <bits/stdc++.h>
#define f first
#define s second
#define pb push_back
#define sz(x) ((int)((x).size()))
#define le(vec) vec[vec.size()-1]
#define all(x) (x).begin(), (x).end()
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr)
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef map<int, int> mii;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;
const int INF=1e9, MOD=1e9+7, mod=998244353;
const ll LINF=1e18;
void setIO()
{
FAST_IO;
}
void setIO(string s)
{
FAST_IO;
freopen((s+".txt").c_str(), "r", stdin);
freopen((s+".out").c_str(), "w", stdout);
}
const int N=1e5+10;
//tot - total amount of leaves in a subtree
//add - number of added leaves to each query for each N node
//bad_ch - number of bad vertices changed during dfs
int n, q, tot[N], bad_ch[N], add_leaves[N], add_edges[N];
mii add[N];
vi ad[N];
void pre(int u, int pst)
{
for(auto x : ad[u]){
if(x==pst) continue;
pre(x, u);
tot[u]+=tot[x];
}
if(sz(ad[u])==1) tot[u]++;
}
void dfs(int u, int pst)
{
for(auto x : ad[u]){
if(x==pst) continue;
dfs(x, u);
}
int mx=-1, mxu=-1;
for(auto x : ad[u]){
if(x==pst) continue;
if(sz(add[x])>mx){
mx=sz(add[x]);
mxu=x;
}
}
swap(add[u], add[mxu]);
for(auto x : ad[u]){
if(x==pst) continue;
for(auto it : add[x]){
add[u][it.f]+=it.s;
}
add[x].clear();
}
for(auto it : add[u]){
if(it.s&1){
if(tot[u]&1){
bad_ch[it.f]++;
}
else{
bad_ch[it.f]--;
}
}
}
}
int main()
{
setIO();
cin >> n >> q;
FOR(i, 0, n-1)
{
int a, b; cin >> a >> b; a--; b--;
ad[a].pb(b);
ad[b].pb(a);
}
pre(0, -1);
FOR(i, 0, q)
{
set<int> st;
int d; cin >> d;
FOR(j, 0, d)
{
int a; cin >> a; --a;
if(sz(ad[a])==1){
if(st.count(a)){
add[a][i]++;
add_leaves[i]++;
}
}
else{
add[a][i]++;
add_leaves[i]++;
}
st.insert(a);
}
add_edges[i]=d;
}
int tot_bad=-1; //(we exclude root as it has no parent vertex)
FOR(i, 0, n)
{
if(tot[i]&1^1){
++tot_bad;
}
}
int tot_leaf=0;
FOR(i, 0, n)
{
if(sz(ad[i])==1){
++tot_leaf;
}
}
dfs(0, -1);
FOR(i, 0, q)
{
if((tot_leaf+add_leaves[i])&1){
cout << "-1\n";
continue;
}
cout << n-1+add_edges[i]+tot_bad+bad_ch[i] << '\n';
}
}
Compilation message
cleaning.cpp: In function 'int main()':
cleaning.cpp:133:18: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
133 | if(tot[i]&1^1){
| ~~~~~~^~
cleaning.cpp: In function 'void setIO(std::string)':
cleaning.cpp:32:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
32 | freopen((s+".txt").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cleaning.cpp:33:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
33 | freopen((s+".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
7380 KB |
Output is correct |
2 |
Incorrect |
81 ms |
11220 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
26 ms |
8148 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
20 ms |
9052 KB |
Output is correct |
2 |
Correct |
21 ms |
9088 KB |
Output is correct |
3 |
Correct |
59 ms |
26124 KB |
Output is correct |
4 |
Correct |
102 ms |
30048 KB |
Output is correct |
5 |
Correct |
48 ms |
24232 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
55 ms |
11496 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
81 ms |
14028 KB |
Output is correct |
2 |
Incorrect |
104 ms |
13396 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
150 ms |
17364 KB |
Output is correct |
2 |
Execution timed out |
1087 ms |
21104 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
7380 KB |
Output is correct |
2 |
Incorrect |
81 ms |
11220 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |