#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define all(a) begin(a),end(a)
const int mxN = (int)2e5+2;
vector<int> v[mxN];
int n, m, ans = mxN;
int col[mxN], sub[mxN], par[mxN], vis[mxN], vis2[mxN];
vector<int> adj[mxN];
int getSub(int s, int p){
sub[s] = 1; par[s]=p;
for(auto u : adj[s])
if(u!=p and !vis[u]) sub[s]+=getSub(u,s);
return sub[s];
}
int findCen(int s, int p, int n){
for(auto u : adj[s])
if(u!=p and !vis[u] and sub[u]>n/2)
return findCen(u,s,n);
return s;
}
void dfs(int s, int p, bool ok){
par[s] = ok?p:-1;
for(auto u : adj[s])
if(u!=p and !vis[u]) dfs(u,s,ok);
}
void cenDec(int cen, int p){
cen = findCen(cen,p,getSub(cen,cen));
dfs(cen,cen,1); vis[cen]=vis2[col[cen]]=1;
queue<int> Q = queue<int>();
bool ok = 1; int cnt = 0;
for(auto u : v[col[cen]]){
if(ok and par[u]>=0) Q.push(u);
else ok=0;
}
while(!Q.empty() and ok){
auto a = Q.front(); Q.pop();
int C = col[a], Cp = col[par[a]];
if(!vis2[Cp]){
for(auto u : v[Cp]){
if(ok and par[u]>=0) Q.push(u);
else ok=0;
}
if(ok) vis2[Cp]=1; cnt++;
}
}
if(ok) ans = min(ans, cnt);
dfs(cen,cen,0);
for(auto u : adj[cen])
if(u!=p and !vis[u]) cenDec(u,cen);
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(0);
cin >> n >> m;
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 >> col[i], v[col[i]].pb(i);
cenDec(1,-1); cout << ans << "\n";
}
Compilation message
capital_city.cpp: In function 'void cenDec(int, int)':
capital_city.cpp:49:4: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
49 | if(ok) vis2[Cp]=1; cnt++;
| ^~
capital_city.cpp:49:23: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
49 | if(ok) vis2[Cp]=1; cnt++;
| ^~~
capital_city.cpp:43:7: warning: unused variable 'C' [-Wunused-variable]
43 | int C = col[a], Cp = col[par[a]];
| ^
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
9660 KB |
Output is correct |
2 |
Correct |
6 ms |
9732 KB |
Output is correct |
3 |
Correct |
5 ms |
9728 KB |
Output is correct |
4 |
Correct |
5 ms |
9684 KB |
Output is correct |
5 |
Correct |
6 ms |
9684 KB |
Output is correct |
6 |
Correct |
6 ms |
9724 KB |
Output is correct |
7 |
Incorrect |
6 ms |
9856 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
9660 KB |
Output is correct |
2 |
Correct |
6 ms |
9732 KB |
Output is correct |
3 |
Correct |
5 ms |
9728 KB |
Output is correct |
4 |
Correct |
5 ms |
9684 KB |
Output is correct |
5 |
Correct |
6 ms |
9684 KB |
Output is correct |
6 |
Correct |
6 ms |
9724 KB |
Output is correct |
7 |
Incorrect |
6 ms |
9856 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
563 ms |
34736 KB |
Output is correct |
2 |
Correct |
187 ms |
38820 KB |
Output is correct |
3 |
Correct |
518 ms |
38224 KB |
Output is correct |
4 |
Correct |
199 ms |
38844 KB |
Output is correct |
5 |
Incorrect |
552 ms |
35808 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
9660 KB |
Output is correct |
2 |
Correct |
6 ms |
9732 KB |
Output is correct |
3 |
Correct |
5 ms |
9728 KB |
Output is correct |
4 |
Correct |
5 ms |
9684 KB |
Output is correct |
5 |
Correct |
6 ms |
9684 KB |
Output is correct |
6 |
Correct |
6 ms |
9724 KB |
Output is correct |
7 |
Incorrect |
6 ms |
9856 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |