#include "bits/stdc++.h"
using namespace std;
#ifdef Nero
#include "Deb.h"
#else
#define deb(...)
#endif
const int LOG = 18;
const int N = 2e5 + 5;
int dep[N];
int root[N];
int color[N];
int up[LOG][N];
set<int> se[N];
int p[N], sz[N];
int p2[N], sz2[N];
vector<int> g[N];
set<int> conn[N];
set<int> times[N];
int ord, in[N], out[N];
bool ineed[N], needme[N];
void dfs(int v, int pr) {
in[v] = ord++;
for (int u : g[v]) {
if (u == pr) continue;
dep[u] = dep[v] + 1;
up[0][u] = v;
for (int j = 1; j < LOG; ++j) {
up[j][u] = up[j - 1][up[j - 1][u]];
}
dfs(u, v);
}
out[v] = ord - 1;
}
int lca(int u, int v) {
if (dep[u] < dep[v]) swap(u, v);
for (int j = 0; j < LOG; ++j) {
if ((dep[u] - dep[v]) >> j & 1) {
u = up[j][u];
}
}
if (u == v) return v;
for (int j = LOG - 1; j >= 0; --j) {
if (up[j][u] != up[j][v]) {
u = up[j][u], v = up[j][v];
}
}
return up[0][v];
}
int get(int v) {
return p[v] = (p[v] == v ? v : get(p[v]));
}
int get2(int v) {
return p2[v] = (p2[v] == v ? v : get2(p2[v]));
}
void unite(int v, int u) {
v = get(v), u = get(u);
if (sz[v] < sz[u]) swap(u, v);
p[u] = v;
sz[v] += sz[u];
root[v] = lca(root[v], root[u]);
for (int w : times[u]) {
times[v].insert(w);
}
}
void unite2(int v, int u) {
v = get2(v); u = get2(u);
if (sz2[v] < sz2[u]) swap(u, v);
p2[u] = v;
sz2[v] += sz2[u];
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n, k;
cin >> n >> k;
for(int i = 0; i < n - 1; ++i) {
int u, v;
cin >> u >> v;
g[u].push_back(v);
g[v].push_back(u);
}
dfs(1, 1);
iota(p + 1, p + 1 + k, 1);
fill(sz + 1, sz + 1 + n, 1);
for (int i = 1; i <= n; ++i) {
cin >> color[i];
times[color[i]].insert(in[i]);
p2[i] = i;
sz2[i] = 1;
if (root[color[i]] == 0) {
root[color[i]] = i;
} else {
root[color[i]] = lca(root[color[i]], i);
}
}
for (int v = 1; v <= n; ++v) {
for (int u : g[v]) {
int pv = get(color[v]), pu = get(color[u]);
if (pv == pu) {//same color
unite2(u, v);
continue;
}
if (u == up[0][v]) {
if (root[pv] != v) {
ineed[pu] = true;
}
continue;
}
auto it = times[pv].lower_bound(in[u]);
if (it != times[pv].end() && *it <= out[u]) {
ineed[pu] = true;
}
if (root[pu] != u) {
needme[pu] = true;
}
}
for (int u : g[v]) {
if (u == up[0][v]) continue;
int pv = get(color[v]), pu = get(color[u]);
if (pv == pu) continue; //same color
if (ineed[pu] && needme[pu]) {
unite(pv, pu);
unite2(v, u);
}
ineed[pu] = needme[pu] = false;
}
}
int ans = k;
for (int i = 1; i <= n; ++i) {
conn[color[i]].insert(get2(i));
}
for (int i = 1; i <= k; ++i) {
if (conn[i].size() == 1) {
ans = min(ans, sz[get(i)]);
}
}
cout << ans - 1 << '\n';
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
53596 KB |
Output is correct |
2 |
Correct |
11 ms |
53736 KB |
Output is correct |
3 |
Correct |
9 ms |
53780 KB |
Output is correct |
4 |
Correct |
10 ms |
53592 KB |
Output is correct |
5 |
Incorrect |
9 ms |
53596 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
53596 KB |
Output is correct |
2 |
Correct |
11 ms |
53736 KB |
Output is correct |
3 |
Correct |
9 ms |
53780 KB |
Output is correct |
4 |
Correct |
10 ms |
53592 KB |
Output is correct |
5 |
Incorrect |
9 ms |
53596 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
313 ms |
101780 KB |
Output is correct |
2 |
Correct |
113 ms |
98908 KB |
Output is correct |
3 |
Incorrect |
369 ms |
101716 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
53596 KB |
Output is correct |
2 |
Correct |
11 ms |
53736 KB |
Output is correct |
3 |
Correct |
9 ms |
53780 KB |
Output is correct |
4 |
Correct |
10 ms |
53592 KB |
Output is correct |
5 |
Incorrect |
9 ms |
53596 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |