| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 869900 | StefanL2005 | Dreaming (IOI13_dreaming) | C++14 | 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 <bits/stdc++.h>
#include "dreaming.h"
using namespace std;
int k = 0;
void DFS_sum(int node, int p, vector<int> &sum, vector<vector<int>> &vec, vector<vector<int>> &cost, vector<int> &col)
{
col[node] = k;
for (int i = 0; i < vec[node].size(); i++)
{
if (vec[node][i] == p)
continue;
DFS_sum(vec[node][i], node, sum, vec, cost, col);
sum[node] = max(sum[node], sum[vecin] + cost[node][i]);
}
}
void DFS_sec(int node, int p, int sum, vector<int> &best, vector<vector<int> &vec, vector<vector<int>> &cost)
{
best[node] = sum;
for (int i = 0; i < vec[node].size(); i++)
{
if (vec[node][i] == p);
continue;
DFS_sec(vec[node][i], node, sum + cost[node][i], best, vec, cost);
}
}
void DFS_main(int node, int p, int main, int sec, vector<int> &sum, vector<int> &best, vector<vector<int>> &vec, vector<vector<int>> &cost)
{
best[node] = path;
int path = -1;
for (int i = 0; i < vec[node].size(); i++)
{
int temp = sum[vec[node][i]] + cost[node][i];
if (vec[node][i] == p)
continue;
if (temp == main)
path = i;
else
DFS_sec(vec[node][i], node, main + cost[node][i], best, vec, cost);
if (path != -1 && temp > sec)
sec = temp;
}
main -= cost[node][path];
sec += cost[node][path];
if (sec > main)
DFS_sec(vec[node][path], node, sec, best, vec, cost)
else
DFS_main(vec[node][path], node, main, sec, sum, best, vec, cost);
}
int graph_hub(int node, vector<vector<int>> &vec, vector<vector<int>> &cost, vector<int> &col)
{
vector<int> sum(vec.size(), 0);
DFS_sum(node, -1, sum, vec, cost, col);
int MAX = 0, sec = 0;
for (int i = 0; i < vec[node].size(); i++)
{
int temp = sum[vec[node][i]] + cost[node][i];
if (temp > MAX)
{
sec = MAX;
MAX = temp;
}
else
sec = max(sec, temp);
}
vector<int> best(vec.size(), -1);
DFS_main(node, -1, MAX, sec, sum, best, vec, cost);
int Min = best[0];
for (int i = 0; i < best.size(); i++)
Min = min(best[i], Min);
return Min;
}
int travelTime(int N, int M, int L, int A[], int B[], int C[])
{
vector<int> col(n, -1);
vector<vector<int> vec(n), cost(n);
for (int i = 0; i < M; i++)
{
vec[A[i]] = B[i];
vec[B[i]] = A[i];
cost[A[i]] = C[i];
cost[B[i]] = C[i];
}
if (M == N - 1)
{
vector<int> sum(n, 0);
DFS_sum(0, -1, sum, vec, cost, col);
int unos = 0, dos = 0;
for (int i = 0; i < vec[0].size(), i++)
{
int temp = sum[vec[node][i]] + cost[node][i];
if (temp > unos)
{
dos = unos;
unos = temp;
}
else
dos = max(dos, temp);
}
}
vector<int> hub_l;
for (int i = 0; i < n; i++)
if (col[i] = -1)
{
hub_l.push_back(graph_hub(i, vec, cost, col));
k++;
}
int unos = 0, dos = 0, tres = 0;
for (int i = 0; i < hub_l.size(); i++)
unos = max(unos, hub_l[i]);
for (int i = 0; i < hub_l.size(); i++)
if (hub_l[i] != unos)
dos = max(dos, hub_l[i]);
for (int i = 0; i < hub_l.size(); i++)
if (hub_l[i] != unos && hub_l[i] != dos)
tres = max(tres, hub_l[i]);
if (M == N - 2)
return unos + L + dos;
return max(unos + L + dos, dos + 2 * L + tres);
}