| # | 제출 시각 | 아이디 | 문제 | 언어 | 결과 | 실행 시간 | 메모리 |
|---|---|---|---|---|---|---|---|
| 651749 | perchuts | 즐거운 행로 (APIO20_fun) | C++17 | 0 ms | 0 KiB |
이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.
#include <bits/stdc++.h>
#define all(x) x.begin(), x.end()
#define sz(x) (int) x.size()
#define endl '\n'
#define pb push_back
#define _ ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ii = pair<int,int>;
using iii = tuple<int,int,int>;
const int mod = 1e9+7;
const int inf = 2e9+1;
const int maxn = 3e5+100;
template<typename X, typename Y> bool ckmin(X& x, const Y& y) { return (y < x) ? (x=y,1):0; }
template<typename X, typename Y> bool ckmax(X& x, const Y& y) { return (x < y) ? (x=y,1):0; }
static void wrongAnswer(std::string message) {
printf("WA: %s\n", message.c_str());
exit(0);
}
namespace tree_helper {
static int N;
static int logN;
static std::vector<std::vector<int>> parent;
static std::vector<int> depth;
static std::vector<int> subtree_size;
static void dfs(
const std::vector<std::vector<int>>& adj_list,
int current_node, int parent_node) {
parent[0][current_node] = parent_node;
subtree_size[current_node] = 1;
for (int i = 0; i < static_cast<int>(adj_list[current_node].size()); ++i) {
const int next_node = adj_list[current_node][i];
if (next_node != parent_node) {
depth[next_node] = depth[current_node] + 1;
dfs(adj_list, next_node, current_node);
subtree_size[current_node] += subtree_size[next_node];
}
}
}
static void initializeTree(const std::vector<std::vector<int>>& adj_list) {
N = static_cast<int>(adj_list.size());
depth = std::vector<int>(N, 0);
subtree_size = std::vector<int>(N, 0);
for (logN = 0; (1 << logN) < N; ++logN) {}
parent = std::vector<std::vector<int>>(logN, std::vector<int>(N, 0));
dfs(adj_list, 0, 0);
for (int i = 1; i < logN; ++i) {
for (int j = 0; j < N; ++j) {
parent[i][j] = parent[i - 1][parent[i - 1][j]];
}
}
}
static int getLowestCommonAncestor(int X, int Y) {
if (depth[X] < depth[Y]) {
std::swap(X, Y);
}
for (int i = logN - 1; i >= 0; --i) {
if (depth[parent[i][X]] >= depth[Y]) {
X = parent[i][X];
}
}
if (X == Y) {
return X;
}
for (int i = logN - 1; i >= 0; --i) {
if (parent[i][X] != parent[i][Y]) {
X = parent[i][X];
Y = parent[i][Y];
}
}
return parent[0][X];
}
static int getDistance(int X, int Y) {
return depth[X] + depth[Y] - 2 * depth[getLowestCommonAncestor(X, Y)];
}
static int attractionsBehind(int X, int Y) {
if (X == Y) {
return N;
}
for (int i = logN - 1; i >= 0; --i) {
if (depth[parent[i][X]] > depth[Y]) {
X = parent[i][X];
}
}
if (Y == parent[0][X]) {
return N - subtree_size[X];
}
return subtree_size[Y];
}
static void checkFunTour(const std::vector<int>& fun_tour) {
if (static_cast<int>(fun_tour.size()) != N) {
wrongAnswer("Invalid size");
}
std::vector<bool> visited_attractions(N, false);
for (int i = 0; i < N; ++i) {
if (fun_tour[i] < 0 || fun_tour[i] >= N) {
wrongAnswer("Invalid index");
}
if (visited_attractions[fun_tour[i]]) {
wrongAnswer("Repeated index");
}
visited_attractions[fun_tour[i]] = true;
}
int last_travel_time = getDistance(fun_tour[0], fun_tour[1]);
for (int i = 2; i < N; ++i) {
int travel_time = getDistance(fun_tour[i - 1], fun_tour[i]);
if (travel_time > last_travel_time) {
wrongAnswer("Tour is not fun");
}
last_travel_time = travel_time;
}
}
} // namespace tree_helper
static int N, Q;
int hoursRequired(int X, int Y) {
if (--Q < 0) {
wrongAnswer("Too many queries");
}
if (X < 0 || X >= N || Y < 0 || Y >= N) {
wrongAnswer("Invalid index");
}
return tree_helper::getDistance(X, Y);
}
int attractionsBehind(int X, int Y) {
if (--Q < 0) {
wrongAnswer("Too many queries");
}
if (X < 0 || X >= N || Y < 0 || Y >= N) {
wrongAnswer("Invalid index");
}
return tree_helper::attractionsBehind(X, Y);
}
vector<int> createFunTour(int N, int Q) {
// assert(N<=500);
vector<int>ans(N), pode(N,1);
vector<vector<int>>dist(N,vector<int>(N,0));
for(int i=0;i<N;++i){
for(int j=i+1;j<N;++j){
dist[i][j] = dist[j][i] = hoursRequired(i,j);
}
}
int best = 0, x = 0;
for(int i=0;i<N;++i)if(dist[0][i]>dist[0][best])best = i;
for(int i=0;i<N;++i)if(dist[best][i]>dist[best][x])x = i;
for(int i=0;i<N;++i){
ans[i] = best, pode[best] = 0, best = -1;
for(int i=0;i<N;++i){
if(pode[i]&&(best==-1||dist[x][i]>dist[x][best]))best = i;
}
swap(x,best);
}
return ans;
}
int main() {
assert(2 == scanf("%d %d", &N, &Q));
std::vector<std::vector<int>> adj_list(N);
for (int i = 0; i < N - 1; ++i) {
int A, B;
assert(2 == scanf("%d %d", &A, &B));
adj_list[A].push_back(B);
adj_list[B].push_back(A);
}
tree_helper::initializeTree(adj_list);
std::vector<int> fun_tour = createFunTour(N, Q);
tree_helper::checkFunTour(fun_tour);
for (int i = 0; i < N; ++i) {
printf("%d%c", fun_tour[i], " \n"[i == N - 1]);
}
return 0;
}