#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define fi first
#define se second
const int maxN=5e5+5,LG=__lg(maxN)+5;
const ll inf=2e18;
int n,k,a[maxN+1],num[maxN+1],timer=0,h[maxN+1],up[maxN+1][LG+1],f[maxN+1];
vector<int> adj[maxN+1],vec[maxN+1],nadj[maxN+1];
void dfs(int u)
{
num[u]=++timer;
for(auto v:adj[u])
{
if(v==up[u][0])
{
continue;
}
up[v][0]=u;
h[v]=h[u]+1;
for(int j=1;j<=LG;j++)
{
up[v][j]=up[up[v][j-1]][j-1];
}
dfs(v);
}
}
int lca(int u,int v)
{
if(h[u]<h[v])
{
swap(u,v);
}
for(int j=LG;j>=0;j--)
{
if(h[up[u][j]]>=up[v][j])
{
u=up[u][j];
}
}
if(u==v)
{
return u;
}
for(int j=LG;j>=0;j--)
{
if(up[u][j]!=up[v][j])
{
u=up[u][j];
v=up[v][j];
}
}
return up[u][0];
}
void dfs1(int u)
{
for(auto v:adj[u])
{
if(v!=up[u][0])
{
dfs1(v);
f[u]+=f[v];
}
}
}
void dfs2(int u)
{
for(auto v:adj[u])
{
if(v!=up[u][0])
{
dfs2(v);
if(!f[v])
{
//cout<<u<<" "<<v<<'\n';
nadj[v].push_back(u);
nadj[u].push_back(v);
}
}
}
}
int main()
{
//freopen("","r",stdin);
//freopen("","w",stdout);
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin>>n>>k;
for(int i=1;i<n;i++)
{
int u,v;
cin>>u>>v;
adj[u].push_back(v);
adj[v].push_back(u);
}
h[1]=1;
dfs(1);
for(int i=1;i<=n;i++)
{
cin>>a[i];
vec[a[i]].push_back(i);
}
for(int i=1;i<=k;i++)
{
sort(vec[i].begin(),vec[i].end(),[&](int x,int y)
{
return num[x]<num[y];
});
int len=vec[i].size();
if(len==1)
{
continue;
}
for(int j=0;j<len;j++)
{
int u=vec[i][j],v=vec[i][(j+1)%len];
f[u]++;
f[lca(u,v)]--;
}
}
dfs1(1);
dfs2(1);
int cnt=0;
for(int i=1;i<=n;i++)
{
cnt+=(nadj[i].size()==1);
}
cout<<(cnt+1)/2;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
35676 KB |
Output is correct |
2 |
Incorrect |
15 ms |
35676 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
35676 KB |
Output is correct |
2 |
Incorrect |
15 ms |
35676 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
35676 KB |
Output is correct |
2 |
Incorrect |
15 ms |
35676 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
84 ms |
52168 KB |
Output is correct |
2 |
Correct |
85 ms |
58052 KB |
Output is correct |
3 |
Incorrect |
17 ms |
36184 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
35676 KB |
Output is correct |
2 |
Incorrect |
15 ms |
35676 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |