| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1260858 | Bui_Quoc_Cuong | Cats or Dogs (JOI18_catdog) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
using namespace std;
template <class A, class B>
bool maximize(A &a, const B b) {
if (a < b) {
a = b;
return true;
} return false;
}
template <class A, class B>
bool minimize(A &a, const B b) {
if (a > b) {
a = b;
return true;
} return false;
}
#define pb push_back
#define FOR(i, a, b) for(int i = a; i <= (int)b; i++)
#define FORD(i, a, b) for(int i = a; i >= (int)b; i--)
#define fi first
#define se second
#define ALL(A) A.begin(), A.end()
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef long long ll;
const int N = 3e5 + 5;
const int oo = 2e9 + 29032008;
const ll INF = 1e18 + 29032008;
int n, q;
vi g[N];
int a[N];
namespace sub1 {
ll dp[N][3];
void dfs(int u, int p) {
if (a[u] == 0 || a[u] == 1) dp[u][1] = 0;
if (a[u] == 0 || a[u] == 2) dp[u][2] = 0;
for (int &v : g[u]) if (v != p) {
dfs(v, u);
dp[u][1]+= min(dp[v][1], dp[v][2] + 1);
dp[u][2]+= min(dp[v][2], dp[v][1] + 1);
}
}
int cat(int u) {
a[u] = 1;
dfs(1, - 1);
return min(dp[1][1], dp[1][2]);
}
int dog(int u) {
a[u] = 2;
dfs(1, - 1);
return min(dp[1][1], dp[1][2]);
}
int neighbor(int u) {
a[u] = 0;
dfs(1, - 1);
return min(dp[1][1], dp[1][2]);
}
void solve() {
while (q--) {
int type, u; cin >> type >> u;
if (type <= 2) a[u] = type;
else a[u] = 0;
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= 2; j++) {
dp[i][j] = 2e9;
}
}
if (type == 1) cout << cat(u);
if (type == 2) cout << dog(u);
if (type == 3) cout << neighbor(u);
cout << "\n";
}
}
}
void initialize(int _N, vector<int> A, vector<int> B){
for(int i = 0; i < n - 1; ++i){
int u = A[i], v = B[i];
g[u].emplace_back(v);
g[v].emplace_back(u);
}
}
void solve() {
cin >> n;
vector <int> A(n - 1), B(n - 1);
for (int i = 0; i < n - 1; i++) {
cin >> A[i] >> B[i];
}
initialize(n, A, B);
cin >> q;
return sub1::solve();
}
signed main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr);
#define ko "kieuoanh"
if (fopen(ko".inp", "r")) {
freopen(ko".inp", "r", stdin);
freopen(ko".out", "w", stdout);
}
int NTEST = 1; // cin >> NTEST;
while (NTEST--) solve();
cerr << "\n[Time Elapsed] " << 0.001 * clock() << "s\n";
return 0;
}