#include <iostream>
#include <vector>
#include "dreaming.h"
#include <climits>
#include <queue>
#include <map>
#include <algorithm>
using namespace std;
vector<int> a, b, w;
vector<vector<int> > adj;
map<pair<int,int>,int> myMap;
vector<bool> hasVisited;
vector<int> parent;
pair<int,int> find_farthest_node (int x, bool undo) {
queue<pair<int,int> > q;
q.push(make_pair(x, 0));
hasVisited[x] = true;
parent[x] = -1;
vector<int> nodes;
vector<pair<int,int> > vec;
while (!q.empty()) {
pair<int,int> p = q.front();
nodes.push_back(p.first);
vec.push_back(make_pair(p.second, p.first));
q.pop();
for (int j: adj[p.first]) {
if (!hasVisited[j]) {
q.push(make_pair(j, p.second + myMap[make_pair(j, p.first)]));
parent[j] = p.first;
hasVisited[j] = true;
}
}
}
if (undo) {
for (int j: nodes) {
hasVisited[j] = false;
}
}
sort(vec.begin(), vec.end());
return vec.back(); //first distance, then node
}
int travelTime (int N, int M, int L, int A[], int B[], int W[]) {
a.resize(M), b.resize(M), w.resize(M), adj.resize(N), parent.resize(N);
for (int i = 0; i < M; i++) {
a[i] = A[i], b[i] = B[i], w[i] = W[i];
myMap[make_pair(a[i], b[i])] = w[i];
myMap[make_pair(b[i], a[i])] = w[i];
adj[a[i]].push_back(b[i]), adj[b[i]].push_back(a[i]);
}
hasVisited.assign(N, false);
vector<int> paths;
int ans = 0;
for (int i = 0; i < N; i++) {
if (!hasVisited[i]) {
int x = find_farthest_node(i, true).second;
pair<int,int> py = find_farthest_node(x, false);
vector<int> nodes;
ans = max(ans, py.first);
int c = 0;
int myMin = INT_MAX;
int best = 0;
for (int j = 1; j < (int)nodes.size(); j++) {
c += myMap[make_pair(nodes[j], nodes[j - 1])];
if (max(c, py.first - c) < myMin) {
myMin = max(c, py.first - c);
best = nodes[j];
}
}
if (nodes.size() == 1) {
myMin = 0;
}
paths.push_back(myMin);
}
}
sort(paths.begin(), paths.end());
//cout << paths.size() << '\n';
if (paths.size() == 1) {
ans = max(ans, paths[0]);
} else if (paths.size() == 2) {
ans = max(paths.back() + paths[paths.size() - 2] + L, ans);
} else {
ans = max(paths.back() + paths[paths.size() - 2] + 2 * L, ans);
}
return ans;
}
/*
int main() {
int N = 12;
int M = 8;
int L = 2;
int A[M], B[M], T[M];
A[0] = 0, A[1] = 8, A[2] = 2, A[3] = 5, A[4] = 5, A[5] = 1, A[6] = 1, A[7] = 10;
B[0] = 8, B[1] = 2, B[2] = 7, B[3] = 11, B[4] = 1, B[5] = 3, B[6] = 9, B[7] = 6;
T[0] = 4, T[1] = 2, T[2] = 4, T[3] = 3, T[4] = 7, T[5] = 1, T[6] = 5, T[7] = 3;
cout << travelTime(N, M, L, A, B, T);
}
*/
Compilation message
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:62:17: warning: variable 'best' set but not used [-Wunused-but-set-variable]
62 | int best = 0;
| ^~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
249 ms |
21328 KB |
Output is correct |
2 |
Correct |
231 ms |
21240 KB |
Output is correct |
3 |
Correct |
161 ms |
13952 KB |
Output is correct |
4 |
Correct |
20 ms |
3364 KB |
Output is correct |
5 |
Correct |
14 ms |
2516 KB |
Output is correct |
6 |
Correct |
33 ms |
4908 KB |
Output is correct |
7 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
340 KB |
Output is correct |
3 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
249 ms |
21328 KB |
Output is correct |
2 |
Correct |
231 ms |
21240 KB |
Output is correct |
3 |
Correct |
161 ms |
13952 KB |
Output is correct |
4 |
Correct |
20 ms |
3364 KB |
Output is correct |
5 |
Correct |
14 ms |
2516 KB |
Output is correct |
6 |
Correct |
33 ms |
4908 KB |
Output is correct |
7 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
101 ms |
9820 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
212 KB |
Output is correct |
2 |
Correct |
0 ms |
340 KB |
Output is correct |
3 |
Incorrect |
1 ms |
212 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
249 ms |
21328 KB |
Output is correct |
2 |
Correct |
231 ms |
21240 KB |
Output is correct |
3 |
Correct |
161 ms |
13952 KB |
Output is correct |
4 |
Correct |
20 ms |
3364 KB |
Output is correct |
5 |
Correct |
14 ms |
2516 KB |
Output is correct |
6 |
Correct |
33 ms |
4908 KB |
Output is correct |
7 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |