#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <bitset>
#define ll long long
#define pii pair<ll, ll>
#define fst first
#define snd second
#define vi vector<ll>
#define vpi vector<pii>
using namespace std;
const ll MX = 1e18;
int n, m, s, t, u, v;
vpi adj[100001] = {};
vpi keepTrack[100001] = {};
vi par[100001] = {};
ll dst[2][100001], ret = MX, dst2[100001] = {};
bitset<100001> bt;
inline void solveSSSP(int s, bool b)
{
priority_queue<pii, vector<pii>, greater<pii>> pq;
for (int i = 0; i < n; i++) dst[b][i] = -1;
pq.push({0, s});
while (pq.size())
{
int u = pq.top().snd; ll c = pq.top().fst; pq.pop();
if (dst[b][u] == -1)
{
// cout << "DIJKSTRA - " << b << " " << u << " " << c << "\n";
dst[b][u] = c;
for (pii v : adj[u]) pq.push({c + v.snd, v.fst});
}
}
}
inline void specialTrav(int s, int t)
{
priority_queue<pii, vector<pii>, greater<pii>> pq;
dst2[s] = 0;
pq.push({0, s});
while (pq.size())
{
int u = pq.top().snd; ll c = pq.top().fst; pq.pop();
if (dst2[u] == c)
{
pii tp1 = {dst[0][u], dst[1][u]}, tp2 = tp1;
keepTrack[u].push_back(tp1);
for (pii &pos : keepTrack[u])
{
pos.fst = min(pos.fst, dst[0][u]); pos.snd = min(pos.snd, dst[1][u]);
if (pos < tp1) tp1 = pos;
if (make_pair(pos.snd, pos.fst) < make_pair(tp2.snd, tp2.fst)) tp2 = pos;
}
if (u == t) break;
for (pii v : adj[u])
{
if (c + v.snd < dst2[v.fst])
{
par[v.fst].clear();
keepTrack[v.fst].clear();
dst2[v.fst] = c + v.snd;
pq.push({c + v.snd, v.fst});
}
if (c + v.snd == dst2[v.fst])
{
keepTrack[v.fst].push_back(tp1);
keepTrack[v.fst].push_back(tp2);
par[v.fst].push_back(u);
}
}
}
}
}
inline void bktrk(int t)
{
for (int i = 0; i < n; i++) dst2[i] = -1;
queue<int> q;
q.push(t);
while (q.size())
{
int u = q.front(); q.pop();
for (auto v : keepTrack[u]) {ret = min(ret, v.fst + v.snd);}
for (auto v : par[u])
{
if (!bt[v]) {bt[v] = 1; q.push(v);}
}
}
}
int main()
{
ios :: sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> m;
cin >> s >> t >> u >> v; s--; t--; u--; v--;
for (int i = 0; i < n; i++)
{
dst[0][i] = dst[1][i] = -1;
dst2[i] = MX;
}
for (int i = 0; i < m; i++)
{
int a, b, c; cin >> a >> b >> c;
adj[a - 1].push_back({b - 1, c});
adj[b - 1].push_back({a - 1, c});
}
solveSSSP(u, 0);
solveSSSP(v, 1);
specialTrav(s, t);
bktrk(t);
/*
for (int i = 0; i < n; i++)
{
cout << "Node " << i << ": \n";
for (auto pos : keepTrack[i])
{
cout << pos.fst << ", " << pos.snd << "\n";
}
}
*/
cout << min(dst[0][v], ret) << "\n";
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
456 ms |
35776 KB |
Output is correct |
2 |
Correct |
416 ms |
33704 KB |
Output is correct |
3 |
Correct |
451 ms |
35840 KB |
Output is correct |
4 |
Correct |
443 ms |
36044 KB |
Output is correct |
5 |
Correct |
417 ms |
33168 KB |
Output is correct |
6 |
Correct |
495 ms |
34028 KB |
Output is correct |
7 |
Correct |
453 ms |
34000 KB |
Output is correct |
8 |
Correct |
396 ms |
33196 KB |
Output is correct |
9 |
Correct |
403 ms |
31292 KB |
Output is correct |
10 |
Correct |
430 ms |
34064 KB |
Output is correct |
11 |
Correct |
194 ms |
25852 KB |
Output is correct |
12 |
Correct |
516 ms |
36288 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
421 ms |
32636 KB |
Output is correct |
2 |
Correct |
426 ms |
33004 KB |
Output is correct |
3 |
Correct |
441 ms |
31808 KB |
Output is correct |
4 |
Correct |
424 ms |
32704 KB |
Output is correct |
5 |
Correct |
431 ms |
33748 KB |
Output is correct |
6 |
Correct |
485 ms |
35900 KB |
Output is correct |
7 |
Correct |
425 ms |
33124 KB |
Output is correct |
8 |
Correct |
442 ms |
32860 KB |
Output is correct |
9 |
Correct |
421 ms |
33724 KB |
Output is correct |
10 |
Correct |
391 ms |
32172 KB |
Output is correct |
11 |
Correct |
177 ms |
27768 KB |
Output is correct |
12 |
Correct |
469 ms |
35968 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
27 ms |
9920 KB |
Output is correct |
2 |
Correct |
4 ms |
7424 KB |
Output is correct |
3 |
Correct |
5 ms |
7424 KB |
Output is correct |
4 |
Correct |
58 ms |
12616 KB |
Output is correct |
5 |
Correct |
29 ms |
10844 KB |
Output is correct |
6 |
Correct |
6 ms |
7552 KB |
Output is correct |
7 |
Correct |
7 ms |
7680 KB |
Output is correct |
8 |
Correct |
8 ms |
7680 KB |
Output is correct |
9 |
Correct |
6 ms |
7552 KB |
Output is correct |
10 |
Correct |
28 ms |
10708 KB |
Output is correct |
11 |
Correct |
4 ms |
7424 KB |
Output is correct |
12 |
Correct |
6 ms |
7424 KB |
Output is correct |
13 |
Correct |
5 ms |
7424 KB |
Output is correct |
14 |
Correct |
6 ms |
7564 KB |
Output is correct |
15 |
Correct |
5 ms |
7552 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
456 ms |
35776 KB |
Output is correct |
2 |
Correct |
416 ms |
33704 KB |
Output is correct |
3 |
Correct |
451 ms |
35840 KB |
Output is correct |
4 |
Correct |
443 ms |
36044 KB |
Output is correct |
5 |
Correct |
417 ms |
33168 KB |
Output is correct |
6 |
Correct |
495 ms |
34028 KB |
Output is correct |
7 |
Correct |
453 ms |
34000 KB |
Output is correct |
8 |
Correct |
396 ms |
33196 KB |
Output is correct |
9 |
Correct |
403 ms |
31292 KB |
Output is correct |
10 |
Correct |
430 ms |
34064 KB |
Output is correct |
11 |
Correct |
194 ms |
25852 KB |
Output is correct |
12 |
Correct |
516 ms |
36288 KB |
Output is correct |
13 |
Correct |
421 ms |
32636 KB |
Output is correct |
14 |
Correct |
426 ms |
33004 KB |
Output is correct |
15 |
Correct |
441 ms |
31808 KB |
Output is correct |
16 |
Correct |
424 ms |
32704 KB |
Output is correct |
17 |
Correct |
431 ms |
33748 KB |
Output is correct |
18 |
Correct |
485 ms |
35900 KB |
Output is correct |
19 |
Correct |
425 ms |
33124 KB |
Output is correct |
20 |
Correct |
442 ms |
32860 KB |
Output is correct |
21 |
Correct |
421 ms |
33724 KB |
Output is correct |
22 |
Correct |
391 ms |
32172 KB |
Output is correct |
23 |
Correct |
177 ms |
27768 KB |
Output is correct |
24 |
Correct |
469 ms |
35968 KB |
Output is correct |
25 |
Correct |
27 ms |
9920 KB |
Output is correct |
26 |
Correct |
4 ms |
7424 KB |
Output is correct |
27 |
Correct |
5 ms |
7424 KB |
Output is correct |
28 |
Correct |
58 ms |
12616 KB |
Output is correct |
29 |
Correct |
29 ms |
10844 KB |
Output is correct |
30 |
Correct |
6 ms |
7552 KB |
Output is correct |
31 |
Correct |
7 ms |
7680 KB |
Output is correct |
32 |
Correct |
8 ms |
7680 KB |
Output is correct |
33 |
Correct |
6 ms |
7552 KB |
Output is correct |
34 |
Correct |
28 ms |
10708 KB |
Output is correct |
35 |
Correct |
4 ms |
7424 KB |
Output is correct |
36 |
Correct |
6 ms |
7424 KB |
Output is correct |
37 |
Correct |
5 ms |
7424 KB |
Output is correct |
38 |
Correct |
6 ms |
7564 KB |
Output is correct |
39 |
Correct |
5 ms |
7552 KB |
Output is correct |
40 |
Correct |
485 ms |
39000 KB |
Output is correct |
41 |
Correct |
357 ms |
31036 KB |
Output is correct |
42 |
Correct |
464 ms |
36636 KB |
Output is correct |
43 |
Correct |
208 ms |
27768 KB |
Output is correct |
44 |
Correct |
187 ms |
27768 KB |
Output is correct |
45 |
Correct |
481 ms |
40144 KB |
Output is correct |
46 |
Correct |
471 ms |
39876 KB |
Output is correct |
47 |
Correct |
515 ms |
41492 KB |
Output is correct |
48 |
Correct |
193 ms |
27128 KB |
Output is correct |
49 |
Correct |
486 ms |
44272 KB |
Output is correct |
50 |
Correct |
475 ms |
40112 KB |
Output is correct |
51 |
Correct |
487 ms |
40112 KB |
Output is correct |