| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 877462 | boris_mihov | Fun Tour (APIO20_fun) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "fun.h"
#include <algorithm>
#include <iostream>
#include <cassert>
#include <numeric>
#include <vector>
#include <queue>
typedef long long llong;
const int MAXN = 100000 + 10;
const int INF = 1e9;
int n;
int sz[MAXN];
int pos[MAXN];
int type[MAXN];
int perm[MAXN];
int depth[MAXN];
std::vector <int> g[MAXN];
int waitlistType = -1;
struct Element
{
int type;
int depth;
int node;
friend bool operator < (const Element &a, const Element & b)
{
return a.depth < b.depth || (a.depth == b.depth && a.node > b.node);
}
};
std::priority_queue <Element> pq;
std::queue <Element> q;
void calcSize(int node, int par)
{
sz[node] = 1;
for (const int &u : g[node])
{
if (u == par)
{
continue;
}
calcSize(u, node);
sz[node] += sz[u];
}
}
int findCentroid(int node, int par)
{
for (const int &u : g[node])
{
if (u != par && sz[u] > n / 2)
{
return findCentroid(u, node);
}
}
return node;
}
void assign(int node, int par, int t)
{
type[node] = t;
depth[node] = depth[par] + 1;
for (const int &u : g[node])
{
if (u == par)
{
continue;
}
assign(u, node, t);
}
}
std::vector <int> createFunTour(int N, int Q)
{
n = N;
for (int i = 1 ; i <= n ; ++i)
{
for (int j = 2 ; j <= n ; ++j)
{
if (hoursRequired(i - 1, j - 1) == 1)
{
g[i].push_back(j);
g[j].push_back(i);
}
}
}
calcSize(1, 0);
int cntr = findCentroid(1, 0);
for (int idx = 0 ; idx < g[cntr].size() ; ++idx)
{
assign(g[cntr][idx], cntr, idx);
}
type[cntr] = g[cntr].size();
std::vector <int> answer;
for (int i = 1 ; i <= n ; ++i)
{
pq.push({type[i], depth[i], i});
}
while (!pq.empty())
{
auto [t, d, node] = pq.top();
pq.pop();
if (waitlistType == t)
{
q.push({t, d, node});
continue;
}
if (waitlistType != -1)
{
answer.push_back(node);
answer.push_back(q.front().node);
q.pop();
if (q.empty())
{
waitlistType = -1;
}
continue;
}
if (answer.size() && type[answer.back()] == t)
{
q.push({t, d, node});
waitlistType = t;
continue;
}
answer.push_back(node);
}
std::vector <int> output;
for (int i = 0 ; i < answer.size() ; ++i)
{
output.push_back(answer[i] - 1);
if (q.size() && (i + 2 > answer.size() || depth[answer[i + 2]] <= q.front().depth) && (type[answer[i]] != q.front().type && type[answer[i + 1]] != q.front().type))
{
output.push_back(q.front().node - 1);
q.pop();
}
}
while (!q.empty())
{
output.push_back(q.front());
q.pop();
}
return output;
}