# include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
//#define int long long
#define pii pair <int, int>
#define pb push_back
const int N = 3e5 + 5;
int t,n,a[N],sz[N],tin,in[N],out[N],p[N],par[N][20],k,x[N],lv[N],deg[N];
vector <int> v[N];
vector <pii> vec[N];
void dfs(int a, int p) {
tin++;
in[a] = tin;
par[a][0] = p;
for (int i = 1; i <= 18; i++) {
if (par[a][i - 1]) par[a][i] = par[par[a][i - 1]][i - 1];
}
lv[a] = lv[p] + 1;
for (int to : v[a]) {
if (to == p) continue;
dfs(to, a);
}
out[a] = tin;
}
void init() {
for (int i = 1; i <= n; i++) {
p[i] = i; sz[i] = 1;
}
}
int get_col(int a) {
if (a == p[a]) return a;
else return p[a] = get_col(p[a]);
}
void col(int a, int b) {
a = get_col(a); b = get_col(b);
if (a == b) return ;
if (lv[a] > lv[b]) swap(a, b);
p[b] = a;
}
void merge(int a, int lc) {
while (get_col(a) != get_col(lc)) {
col(a, par[get_col(a)][0]);
}
}
int upper(int a, int b) {
return (in[a] <= in[b] && out[a] >= out[b]);
}
int lca(int a, int b) {
if (upper(a, b)) return a;
for (int i = 18; i >= 0; i--) {
if (par[a][i] && !upper(par[a][i], b)) a = par[a][i];
}
return par[a][0];
}
main() {
std::ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0);
cin>>n>>k;
vector <pii> edges;
for (int i = 1; i <= n - 1; i++) {
int a, b;
cin>>a>>b;
v[a].pb(b);
v[b].pb(a);
edges.pb({a,b});
}
dfs(1, 0);
for (int i = 1; i <= n; i++) {
cin>>x[i];
}
init();
for (int i = 1; i <= n; i++) {
vec[x[i]].pb({in[i], i});
}
for (int i = 1; i <= k; i++) {
for (int j = 0; j < vec[i].size(); j++) {
int a = vec[i][j].s, b = vec[i][(j + 1) % vec[i].size()].s, lc = lca(a, b);
merge(a, lc); merge(b, lc);
}
}
for (pii sth : edges) {
if (get_col(sth.f) != get_col(sth.s)) {
deg[sth.f]++; deg[sth.s]++;
}
}
int cnt = 0;
for (int i = 1; i <= n; i++) {
cnt += (int)(deg[i] == 1);
}
cout<<(cnt + 1) / 2<<"\n";
}
Compilation message
mergers.cpp:56:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
56 | main() {
| ^~~~
mergers.cpp: In function 'int main()':
mergers.cpp:76:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
76 | for (int j = 0; j < vec[i].size(); j++) {
| ~~^~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
14420 KB |
Output is correct |
2 |
Correct |
8 ms |
14476 KB |
Output is correct |
3 |
Incorrect |
8 ms |
14420 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
14420 KB |
Output is correct |
2 |
Correct |
8 ms |
14476 KB |
Output is correct |
3 |
Incorrect |
8 ms |
14420 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
14420 KB |
Output is correct |
2 |
Correct |
8 ms |
14476 KB |
Output is correct |
3 |
Incorrect |
8 ms |
14420 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
87 ms |
31436 KB |
Output is correct |
2 |
Correct |
85 ms |
34168 KB |
Output is correct |
3 |
Incorrect |
10 ms |
14932 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
14420 KB |
Output is correct |
2 |
Correct |
8 ms |
14476 KB |
Output is correct |
3 |
Incorrect |
8 ms |
14420 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |