#include<bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define pb push_back
#define sz(x) (int)(x.size())
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define vi vector<int>
#define vp vector<pii>
#define vvi vector<vi>
#define ykh mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count())
#define __lg(x) 63-__builtin_clzll(x)
#define pow2(x) (1LL<<x)
void __print(int x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef local
void setio(){freopen("/Users/iantsai/Library/Mobile Documents/com~apple~CloudDocs/cpp/Empty.md","r",stdin);}
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
void setio(){}
#define debug(x...)
#endif
void setIO(string s) {
freopen((s + ".in").c_str(), "r", stdin);
freopen((s + ".out").c_str(), "w", stdout);
}
struct line{
int a,b;
int operator()(const int x)const{
return a*x+b;
}
};
bool check(line l1,line l2,line l3){
return (l3.b-l2.b)*(l1.a-l2.a)<=(l2.b-l1.b)*(l2.a-l3.a);
}
const int mxn=2e5+5;
vector<int>adj[mxn];
vector<int>g[mxn];
int c[mxn];
bool vis[mxn];
int cnt[mxn];
bool used[mxn];
bool in[mxn];
int p[mxn];
vector<int>sir;
void cnt_sz(int v,int pa){
cnt[v]=1;
in[v]=1;
p[v]=pa;
sir.pb(v);
for(auto u:adj[v]){
if(u==pa or vis[u])continue;
cnt_sz(u,v);
cnt[v]+=cnt[u];
}
}
int find(int v,int pa,int tar){
for(auto u:adj[v]){
if(vis[u] or u==pa)continue;
if(cnt[u]*2>tar)return find(u,v,tar);
}
return v;
}
int ans;
void cen(int v){
cnt_sz(v,v);
v=find(v,v,cnt[v]);
debug(v);
vis[v]=1;
queue<int>q;
q.push(c[v]);
used[c[v]]=1;
vector<int>undo;
undo.pb(c[v]);
while(sz(q)){
int color=q.front();
q.pop();
for(auto u:g[color]){
if(!in[u]){
goto done;
}
if(p[u]!=u and !used[c[p[u]]]){
q.push(c[p[u]]);
used[c[p[u]]]=1;
undo.pb(c[p[u]]);
}
}
}
chmin(ans,sz(undo)-1);
done:
while(sz(undo)){
used[undo.back()]=0;
undo.pop_back();
}
while(sz(sir)){
in[sir.back()]=0;
sir.pop_back();
}
for(auto u:adj[v]){
if(vis[u])continue;
cen(u);
}
}
signed main(){
setio();
ios::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
int n,k;
cin>>n>>k;
for(int i=1;i<n;i++){
int a,b;
cin>>a>>b;
adj[a].pb(b);
adj[b].pb(a);
}
for(int i=1;i<=n;i++){
cin>>c[i];
g[c[i]].pb(i);
}
ans=k-1;
cen(1);
cout<<ans<<'\n';
}
/*
input:
*/
Compilation message
capital_city.cpp: In function 'void setIO(std::string)':
capital_city.cpp:42:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
42 | freopen((s + ".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
capital_city.cpp:43:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
43 | freopen((s + ".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
14936 KB |
Output is correct |
| 2 |
Correct |
4 ms |
14940 KB |
Output is correct |
| 3 |
Correct |
3 ms |
14940 KB |
Output is correct |
| 4 |
Incorrect |
5 ms |
14940 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
14936 KB |
Output is correct |
| 2 |
Correct |
4 ms |
14940 KB |
Output is correct |
| 3 |
Correct |
3 ms |
14940 KB |
Output is correct |
| 4 |
Incorrect |
5 ms |
14940 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
289 ms |
46668 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
14936 KB |
Output is correct |
| 2 |
Correct |
4 ms |
14940 KB |
Output is correct |
| 3 |
Correct |
3 ms |
14940 KB |
Output is correct |
| 4 |
Incorrect |
5 ms |
14940 KB |
Output isn't correct |
| 5 |
Halted |
0 ms |
0 KB |
- |
