// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>
using namespace std;
#define nl '\n'
#define pb push_back
#define pf push_front
#define mp make_pair
#define f first
#define s second
#define sz(x) int(x.size())
template<class T> using V = vector<T>;
using pi = pair<int, int>;
using vi = V<int>;
using vpi = V<pi>;
using ll = long long;
using pl = pair<ll, ll>;
using vpl = V<pl>;
using vl = V<ll>;
using db = long double;
template<class T> using pq = priority_queue<T, V<T>, less<T>>;
const int MOD = 1e9 + 7;
const ll INFL = ll(1e17);
const int LG = 19;
int main() {
cin.tie(0)->sync_with_stdio(0);
int N, K; cin >> N >> K;
V<vi> adj(N); for(int i = 0; i < N - 1; i++) {
int u, v; cin >> u >> v; --u, --v;
adj[u].pb(v);
adj[v].pb(u);
}
vi A(N); for(auto& x : A) { cin >> x; --x; }
int R = -1; for(int i = 0; i < N; i++) if (sz(adj[i]) >= 2) { R = i; break; }
if (R == -1) {
if (N == 1) cout << 0 << nl;
else {
if (A.front() == A.back()) cout << 0 << nl;
else cout << 1 << nl;
}
exit(0-0);
}
V<vi> up(N, vi(LG)); vi dep(N);
function<void(int, int)> gen = [&](int u, int p) {
up[u][0] = p; dep[u] = (u == p ? 0 : dep[p] + 1);
for(int i = 1; i < LG; i++) up[u][i] = up[up[u][i-1]][i-1];
for(auto& v : adj[u]) if (v != p) gen(v, u);
};
auto jmp = [&](int u, int d) {
for(int i = 0; i < LG; i++) if ((d >> i) & 1) u = up[u][i];
return u;
};
auto lca = [&](int a, int b) {
if (dep[a] < dep[b]) swap(a, b);
a = jmp(a, dep[a] - dep[b]);
if (a == b) return a;
for(int i = LG - 1; i >= 0; i--) {
if (up[a][i] != up[b][i]) a = up[a][i], b = up[b][i];
}
return up[a][0];
};
gen(R, R);
vi L(K, -1); for(int u = 0; u < N; u++) {
if (L[A[u]] == -1) L[A[u]] = u;
else L[A[u]] = lca(L[A[u]], u);
}
// cerr << "R: " << R << endl;
int ans = 0; vi U(N);
function<int(int, int)> dfs = [&](int u, int p) {
int amt = 0; U[u] = L[A[u]];
for(auto& v : adj[u]) if (v != p) {
amt += dfs(v, u);
U[u] = lca(U[u], U[v]);
}
if (U[u] == u) {
// cout << u << " => " << amt << endl;
ans += amt / 2;
if (u == R) ans += amt % 2;
amt = 1;
}
return amt;
};
dfs(R, R);
cout << ans << nl;
exit(0-0);
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
1 ms |
340 KB |
Output is correct |
| 3 |
Correct |
1 ms |
212 KB |
Output is correct |
| 4 |
Correct |
1 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
212 KB |
Output is correct |
| 6 |
Correct |
1 ms |
340 KB |
Output is correct |
| 7 |
Correct |
1 ms |
260 KB |
Output is correct |
| 8 |
Correct |
0 ms |
212 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
320 KB |
Output is correct |
| 11 |
Correct |
1 ms |
340 KB |
Output is correct |
| 12 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 13 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
1 ms |
340 KB |
Output is correct |
| 3 |
Correct |
1 ms |
212 KB |
Output is correct |
| 4 |
Correct |
1 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
212 KB |
Output is correct |
| 6 |
Correct |
1 ms |
340 KB |
Output is correct |
| 7 |
Correct |
1 ms |
260 KB |
Output is correct |
| 8 |
Correct |
0 ms |
212 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
320 KB |
Output is correct |
| 11 |
Correct |
1 ms |
340 KB |
Output is correct |
| 12 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 13 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
1 ms |
340 KB |
Output is correct |
| 3 |
Correct |
1 ms |
212 KB |
Output is correct |
| 4 |
Correct |
1 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
212 KB |
Output is correct |
| 6 |
Correct |
1 ms |
340 KB |
Output is correct |
| 7 |
Correct |
1 ms |
260 KB |
Output is correct |
| 8 |
Correct |
0 ms |
212 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
320 KB |
Output is correct |
| 11 |
Correct |
1 ms |
340 KB |
Output is correct |
| 12 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 13 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
58 ms |
20516 KB |
Output is correct |
| 2 |
Correct |
73 ms |
20768 KB |
Output is correct |
| 3 |
Incorrect |
2 ms |
852 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
1 ms |
340 KB |
Output is correct |
| 3 |
Correct |
1 ms |
212 KB |
Output is correct |
| 4 |
Correct |
1 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
212 KB |
Output is correct |
| 6 |
Correct |
1 ms |
340 KB |
Output is correct |
| 7 |
Correct |
1 ms |
260 KB |
Output is correct |
| 8 |
Correct |
0 ms |
212 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
320 KB |
Output is correct |
| 11 |
Correct |
1 ms |
340 KB |
Output is correct |
| 12 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
| 13 |
Halted |
0 ms |
0 KB |
- |
