#include<bits/stdc++.h>
#define fr first
#define sc second
using namespace std;
void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
typedef long long ll;
#define USING_ORDERED_SET 0
#if USING_ORDERED_SET
#include<bits/extc++.h>
using namespace __gnu_pbds;
template<class T>using ordered_set=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
#endif
template<class T>void umax(T &a,T b){if(a<b)a=b;}
template<class T>void umin(T &a,T b){if(b<a)a=b;}
#ifdef IOI2021SG
#define printl(args...)printf(args)
#else
#define printl(args...)((void)0)
#endif
int n,k;
int tin[200005],tout[200005],timer,up[200005][18];
vector<int>g[200005],color[200005],g1[200005],g2[200005],gr[200005];
int mn[200005][18];
int mx[200005][18];
int a[200005];
void dfs(int v,int p){
tin[v]=++timer;
up[v][0]=p;
mn[v][0]=::a[v];
mx[v][0]=::a[v];
for(int i=1;i<18;i++){
up[v][i]=up[up[v][i-1]][i-1];
mn[v][i]=min(mn[v][i-1],mn[up[v][i-1]][i-1]);
mx[v][i]=max(mx[v][i-1],mx[up[v][i-1]][i-1]);
}
for(int to:g[v])if(to!=p)dfs(to,v);
tout[v]=++timer;
}
bool upper(int a,int b){
return tin[a]<=tin[b]&&tout[a]>=tout[b];
}
int lca(int a,int b){
if(upper(a,b))return a;
if(upper(b,a))return b;
for(int i=17;i>=0;i--)if(!upper(up[a][i],b))a=up[a][i];
return up[a][0];
}
int lca(vector<int>&vec){
int l=vec[0];
for(int i=1;i<(int)vec.size();i++)l=lca(l,vec[i]);
return l;
}
unordered_map<int,bool>vs[200005];
vector<pair<int,int>>edges;
void add_edge(int a,int b){
if(a^b){
if(vs[a][b])return;
vs[a][b]=true;
edges.emplace_back(a,b);
g1[a].push_back(b);
gr[b].push_back(a);
}
}
void add(int v,int a,int l){
for(int i=17;i>=0;i--)
if(mx[a][i]==mn[a][i])a=up[a][i];
if(upper(a,l)&&a!=l)return;
add_edge(v,::a[a]);
}
int cnt=0;
bool vis[200005];
int last;
int sz[200005];
int id[200005];
bool used[200005];
vector<int>order;
void run(int v){
used[v]=true;
for(int to:g1[v])if(!used[to])run(to);
order.push_back(v);
}
void runner(int v){
used[v]=true;
sz[last]++;
id[v]=last;
for(int to:gr[v])if(!used[to])run(to);
}
int dp[200005];
int goo(int v){
if(~dp[v])return dp[v];
dp[v]=sz[v];
for(int to:g2[v])dp[v]+=goo(to);
return dp[v];
}
int main(){
memset(dp,-1,sizeof dp);
scanf("%d%d",&n,&k);
for(int i=1;i<n;i++){
int x,y;
scanf("%d%d",&x,&y);
g[x].push_back(y);
g[y].push_back(x);
}
for(int i=1;i<=n;i++){
scanf("%d",&a[i]);
color[a[i]].push_back(i);
}
dfs(1,1);
for(int i=1;i<=k;i++){
int l=lca(color[i]);
for(int j=0;j<(int)color[i].size();j++)add(i,color[i][j],l);
}
for(int i=1;i<=k;i++)if(!used[i])run(i);
for(int i=1;i<=k;i++)used[i]=0;
for(int i=1;i<=k;i++){
int v=order[k-i];
if(!used[v]){
last++;
runner(v);
}
}
for(auto to:edges)if(id[to.fr]^id[to.sc]){
g2[id[to.fr]].push_back(id[to.sc]);
}
int ans=k;
for(int i=1;i<=last;i++)umin(ans,goo(i));
printf("%d",ans-1);
}
Compilation message
capital_city.cpp: In function 'void usaco(std::string)':
capital_city.cpp:5:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
capital_city.cpp:5:66: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
5 | void usaco(string s){freopen((s+".in").c_str(),"r",stdin);freopen((s+".out").c_str(),"w",stdout);}
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
capital_city.cpp: In function 'int main()':
capital_city.cpp:99:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
99 | scanf("%d%d",&n,&k);
| ~~~~~^~~~~~~~~~~~~~
capital_city.cpp:102:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
102 | scanf("%d%d",&x,&y);
| ~~~~~^~~~~~~~~~~~~~
capital_city.cpp:107:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
107 | scanf("%d",&a[i]);
| ~~~~~^~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
35532 KB |
Output is correct |
| 2 |
Correct |
21 ms |
35660 KB |
Output is correct |
| 3 |
Correct |
21 ms |
35484 KB |
Output is correct |
| 4 |
Incorrect |
26 ms |
35588 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
35532 KB |
Output is correct |
| 2 |
Correct |
21 ms |
35660 KB |
Output is correct |
| 3 |
Correct |
21 ms |
35484 KB |
Output is correct |
| 4 |
Incorrect |
26 ms |
35588 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
610 ms |
127140 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
23 ms |
35532 KB |
Output is correct |
| 2 |
Correct |
21 ms |
35660 KB |
Output is correct |
| 3 |
Correct |
21 ms |
35484 KB |
Output is correct |
| 4 |
Incorrect |
26 ms |
35588 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
