#include <bits/stdc++.h>
using namespace std;
const int mxn=5e5+5;
int n,par[mxn][22],num[mxn],k,s[mxn],st[mxn],fn[mxn],cnt=0,sz[mxn],comp[mxn],ans=0;
bool marky[mxn];
struct yall{
int u,uu;
}yal[mxn];
vector<int>v[mxn],act[mxn];
void pre(int z){
st[z]=++cnt;
act[s[z]].push_back(z);
for(int i=1;i<=21;i++)
par[z][i]=par[par[z][i-1]][i-1];
for(auto i:v[z]){
int x=yal[i].u^yal[i].uu^z;
if(par[z][0]!=x){
par[x][0]=z;
pre(x);
}
}
if(act[s[z]].back()==z)num[z]--;
fn[z]=cnt;
}
int lca(int x,int y){
if(st[x]<=st[y] && fn[x]>=fn[y])return x;
for(int i=21;i>=0;i--){
if(par[x][i]==0)continue;
if(st[par[x][i]]>st[y] || fn[par[x][i]]<st[y])x=par[x][i];
}
return par[x][0];
}
void dfs(int z,int sum=0,int y=0){
if(sum==0 && z!=1)
marky[y]=1;
sum+=num[z];
for(auto i:v[z]){
int x=yal[i].u^yal[i].uu^z;
if(x!=par[z][0]){
dfs(x,sum,i);
}
}
sum-=num[z];
}
void fds(int z){
comp[z]=cnt;
for(auto i:v[z]){
int x=yal[i].u^yal[i].uu^z;
if(!comp[x] && !marky[i])
fds(x);
}
}
int main(){
cin>>n>>k;
for(int i=1;i<n;i++){
cin>>yal[i].u>>yal[i].uu;
v[yal[i].u].push_back(i);
v[yal[i].uu].push_back(i);
}
for(int i=1;i<=n;i++)
cin>>s[i];
pre(1);
for(int i=1;i<=k;i++){
int a=lca(act[i][0],act[i].back());
num[a]++;
}
dfs(1);
cnt=1;
for(int i=1;i<=n;i++){
if(!comp[i]){
fds(i);
cnt++;
}
}
for(int i=1;i<n;i++){
if(marky[i]){
sz[comp[yal[i].u]]++;
sz[comp[yal[i].uu]]++;
}
}
for(int i=1;i<=cnt;i++){
if(sz[i]==1)ans++;
}
cout<<(ans)/2<<endl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
7 ms |
31324 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
7 ms |
31324 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
7 ms |
31324 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
93 ms |
45936 KB |
Output is correct |
2 |
Incorrect |
117 ms |
52292 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
7 ms |
31324 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |