#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
const int mx = 100'000;
const int lg = 17;
using vi = vector<int>;
using vvi = vector<vi>;
#define sz(x) int(x.size())
vi edge[1+mx];
vvi anc(1+mx, vi(1+lg, 0));
vi order(1, 0);
vi order_index(1+mx, 0);
vi depth(1+mx, 0);
vi leaf(1+mx, 0);
vi st_leaf(1+mx, 0);
void dfs(int u)
{
order_index[u] = sz(order);
order.push_back(u);
st_leaf[u] = leaf[u];
for(int v: edge[u])
{
if(anc[u][0] == v) continue;
depth[v] = 1 + depth[u];
anc[v][0] = u;
dfs(v);
st_leaf[u] += st_leaf[v];
}
}
int ancestor(int u, int k)
{
for(int e = 0; e <= lg; e++)
if(k & (1<<e))
u = anc[u][e];
return u;
}
int lca(int u, int v)
{
if(depth[v] < depth[u]) swap(u, v);
v = ancestor(v, depth[v] - depth[u]);
if(u == v) return u;
for(int e = lg; e >= 0; e--)
{
if(anc[u][e] == anc[v][e]) continue;
u = anc[u][e];
v = anc[v][e];
}
return u;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int N, Q;
cin >> N >> Q;
for(int e = 1; e <= N-1; e++)
{
int u, v;
cin >> u >> v;
edge[u].push_back(v);
edge[v].push_back(u);
}
for(int i = 1; i <= N; i++)
if(sz(edge[i]) == 1)
leaf[i] = 1;
int rt = 1;
while(leaf[rt]) rt++;
dfs(rt);
for(int e = 1; e <= lg; e++)
for(int i = 1; i <= N; i++)
anc[i][e] = anc[ anc[i][e-1] ][e-1];
// cerr << "root = " << rt << '\n';
// for(int i = 1; i <= N; i++) cerr << i << " : " << leaf[i] << ' ' << st_leaf[i] << '\n';
for(int q = 1; q <= Q; q++)
{
int D;
cin >> D;
vi new_leaf = leaf;
vi new_st_leaf = st_leaf;
int extra_odd = 0;
for(int d = 1; d <= D; d++)
{
int a;
cin >> a;
int delta = 0;
if(new_leaf[a])
{
new_leaf[a] = 0;
// new_st_leaf[a]--;
delta--;
}
delta++;
extra_odd++;
for(int z = a; z != 0; z = anc[z][0])
{
new_st_leaf[z] += delta;
}
// cerr << a << " : " << "delta = " << delta << '\n';
}
// for(int i = 1; i <= N; i++) cerr << i << " : " << new_leaf[i] << ' ' << new_st_leaf[i] << '\n';
if(new_st_leaf[rt] % 2 == 1) cout << "-1\n";
else
{
int ans = extra_odd;
for(int i = 1; i <= N; i++)
if(i != rt)
ans += vi{2, 1}[new_st_leaf[i] % 2];
cout << ans << '\n';
}
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
10 ms |
15188 KB |
Output is correct |
2 |
Execution timed out |
1073 ms |
16784 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
19 ms |
15708 KB |
Output is correct |
2 |
Correct |
24 ms |
15724 KB |
Output is correct |
3 |
Correct |
59 ms |
19952 KB |
Output is correct |
4 |
Correct |
50 ms |
19144 KB |
Output is correct |
5 |
Correct |
76 ms |
20420 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
842 ms |
16132 KB |
Output is correct |
2 |
Correct |
830 ms |
16132 KB |
Output is correct |
3 |
Correct |
639 ms |
26164 KB |
Output is correct |
4 |
Execution timed out |
1068 ms |
25352 KB |
Time limit exceeded |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1056 ms |
17112 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1096 ms |
18620 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
1058 ms |
20692 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
10 ms |
15188 KB |
Output is correct |
2 |
Execution timed out |
1073 ms |
16784 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |