#include <bits/stdc++.h>
using namespace std;
const int MAXN = 205;
const int MAXM = 50005;
int N, M;
vector<int> adj[MAXN];
vector<int> radj[MAXN];
vector<array<int, 4>> edge;
int par[5][MAXN];
int dist[5][MAXN];
int sptree[5][MAXM];
int Dijkstra(int s, int k, vector<int> a[MAXN], int block = -1, int ru = -1, int rv = -1, int rc = -1, int target = -1) {
for (int i = 0; i < MAXN; i++) {
dist[k][i] = 2e9;
}
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> pq;
pq.emplace(0, s);
auto dt = dist[k];
auto pr = par[k];
dt[s] = 0;
pr[s] = -1;
while (!pq.empty()) {
int u = pq.top().second;
int d = pq.top().first;
pq.pop();
if (dt[u] != d) {
continue;
}
if (u == target) {
return d;
}
if (pr[u] != -1) {
sptree[k][pr[u]] = 1;
}
for (auto e : a[u]) if (e != block) {
int v = edge[e][0] ^ edge[e][1] ^ u;
if (dt[v] > dt[u] + edge[e][2]) {
dt[v] = dt[u] + edge[e][2];
pr[v] = e;
pq.emplace(dt[v], v);
}
}
if (u == ru) {
int v = rv;
if (dt[v] > dt[u] + rc) {
dt[v] = dt[u] + rc;
pr[v] = -1;
pq.emplace(dt[v], v);
}
}
}
return 2e9;
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0), cout.tie(0);
cin >> N >> M;
for (int i = 0; i < M; i++) {
int u, v, c, d;
cin >> u >> v >> c >> d;
edge.push_back({u, v, c, d});
adj[u].emplace_back(i);
radj[v].emplace_back(i);
}
Dijkstra(1, 0, adj); // 1 to N
Dijkstra(N, 1, adj); // N to 1
Dijkstra(N, 2, radj); // 1 to N, reverse
Dijkstra(1, 3, radj); // N to 1, reverse
int ans = (int) min((long long) 2e9, 1ll * dist[0][N] + 1ll * dist[1][1]);
for (int i = 0; i < M; i++) {
int u, v, c, d;
u = edge[i][0], v = edge[i][1], c = edge[i][2], d = edge[i][3];
if (sptree[0][i] == 0 && sptree[1][i] == 0) {
int d1 = min((long long) dist[0][N], (long long) dist[0][v] + c + dist[2][u]);
int d2 = min((long long) dist[1][1], (long long) dist[1][v] + c + dist[3][u]);
if (d1 < 2e9 && d2 < 2e9) {
ans = min(ans, d + d1 + d2);
}
} else {
// int d1 = Dijkstra(1, 4, adj, i, v, u, c, N);
// int d2 = Dijkstra(N, 4, adj, i, v, u, c, 1);
// if (d1 < 2e9 && d2 < 2e9) {
// ans = min(ans, d + d1 + d2);
// }
}
}
if (ans >= 2e9) {
ans = -1;
}
cout << ans << "\n";
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
384 KB |
Output is correct |
3 |
Correct |
5 ms |
384 KB |
Output is correct |
4 |
Correct |
6 ms |
384 KB |
Output is correct |
5 |
Incorrect |
6 ms |
384 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
31 ms |
2548 KB |
Output is correct |
2 |
Correct |
27 ms |
2548 KB |
Output is correct |
3 |
Correct |
28 ms |
2544 KB |
Output is correct |
4 |
Correct |
6 ms |
512 KB |
Output is correct |
5 |
Correct |
5 ms |
384 KB |
Output is correct |
6 |
Correct |
5 ms |
384 KB |
Output is correct |
7 |
Correct |
5 ms |
384 KB |
Output is correct |
8 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
9 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
512 KB |
Output is correct |
2 |
Correct |
5 ms |
384 KB |
Output is correct |
3 |
Correct |
21 ms |
2076 KB |
Output is correct |
4 |
Correct |
5 ms |
384 KB |
Output is correct |
5 |
Correct |
26 ms |
2548 KB |
Output is correct |
6 |
Correct |
5 ms |
384 KB |
Output is correct |
7 |
Correct |
5 ms |
384 KB |
Output is correct |
8 |
Correct |
25 ms |
2396 KB |
Output is correct |
9 |
Correct |
26 ms |
2388 KB |
Output is correct |
10 |
Correct |
26 ms |
2420 KB |
Output is correct |
11 |
Correct |
27 ms |
2412 KB |
Output is correct |
12 |
Correct |
27 ms |
2548 KB |
Output is correct |
13 |
Incorrect |
5 ms |
384 KB |
Output isn't correct |
14 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
384 KB |
Output is correct |
3 |
Correct |
5 ms |
384 KB |
Output is correct |
4 |
Correct |
6 ms |
384 KB |
Output is correct |
5 |
Incorrect |
6 ms |
384 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |