#include <queue>
#include <vector>
#include <iostream>
using namespace std;
const int inf = 1012345678;
vector<int> shortest_path(int src, vector<vector<int> > &G) {
int N = G.size();
vector<int> dist(N, inf);
queue<int> que;
que.push(src);
dist[src] = 0;
while (!que.empty()) {
int u = que.front(); que.pop();
for (int i : G[u]) {
if (dist[i] == inf) {
dist[i] = dist[u] + 1;
que.push(i);
}
}
}
return dist;
}
int main() {
cin.tie(0);
ios_base::sync_with_stdio(false);
int N, M;
cin >> N >> M;
int S, D, A, B;
cin >> S >> D >> A >> B; --S, --D, --A, --B;
vector<vector<int> > G(N);
for (int i = 0; i < M; ++i) {
int a, b;
cin >> a >> b; --a, --b;
G[a].push_back(b);
G[b].push_back(a);
}
vector<int> da = shortest_path(A, G);
vector<int> db = shortest_path(B, G);
if (da[S] != db[S] || da[D] != db[D]) {
int ans = min(da[D] - da[S], db[D] - db[S]);
cout << (ans < 0 ? -1 : ans) << endl;
}
else {
vector<int> ds = shortest_path(S, G);
vector<int> dd = shortest_path(D, G);
int mins = inf, mind = inf;
for (int i = 0; i < N; ++i) {
if (da[i] == db[i]) {
if (da[i] + ds[i] == da[S]) mins = min(mins, da[i]);
if (da[i] + dd[i] == da[D]) mind = min(mind, da[i]);
}
}
int ans = da[D] - da[S] - (mins > mind ? 1 : 0);
cout << (ans < 0 ? -1 : ans) << endl;
}
return 0;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
3 ms |
384 KB |
Output is correct |
| 2 |
Correct |
2 ms |
384 KB |
Output is correct |
| 3 |
Correct |
2 ms |
384 KB |
Output is correct |
| 4 |
Correct |
2 ms |
384 KB |
Output is correct |
| 5 |
Correct |
2 ms |
384 KB |
Output is correct |
| 6 |
Correct |
2 ms |
356 KB |
Output is correct |
| 7 |
Correct |
2 ms |
384 KB |
Output is correct |
| 8 |
Correct |
2 ms |
384 KB |
Output is correct |
| 9 |
Correct |
2 ms |
384 KB |
Output is correct |
| 10 |
Correct |
2 ms |
384 KB |
Output is correct |
| 11 |
Correct |
3 ms |
384 KB |
Output is correct |
| 12 |
Correct |
2 ms |
384 KB |
Output is correct |
| 13 |
Correct |
3 ms |
384 KB |
Output is correct |
| 14 |
Correct |
2 ms |
384 KB |
Output is correct |
| 15 |
Correct |
2 ms |
384 KB |
Output is correct |
| 16 |
Correct |
3 ms |
384 KB |
Output is correct |
| 17 |
Correct |
3 ms |
384 KB |
Output is correct |
| 18 |
Correct |
2 ms |
384 KB |
Output is correct |
| 19 |
Correct |
3 ms |
384 KB |
Output is correct |
| 20 |
Correct |
2 ms |
384 KB |
Output is correct |
| 21 |
Correct |
3 ms |
384 KB |
Output is correct |
| 22 |
Correct |
3 ms |
384 KB |
Output is correct |
| 23 |
Correct |
2 ms |
384 KB |
Output is correct |
| 24 |
Correct |
3 ms |
512 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
36 ms |
3276 KB |
Output is correct |
| 2 |
Correct |
34 ms |
4472 KB |
Output is correct |
| 3 |
Correct |
27 ms |
3320 KB |
Output is correct |
| 4 |
Correct |
31 ms |
4736 KB |
Output is correct |
| 5 |
Correct |
36 ms |
2816 KB |
Output is correct |
| 6 |
Correct |
27 ms |
3200 KB |
Output is correct |
| 7 |
Correct |
26 ms |
3968 KB |
Output is correct |
| 8 |
Correct |
30 ms |
3832 KB |
Output is correct |
| 9 |
Correct |
42 ms |
4216 KB |
Output is correct |
| 10 |
Correct |
186 ms |
8892 KB |
Output is correct |
| 11 |
Correct |
63 ms |
6748 KB |
Output is correct |
| 12 |
Correct |
89 ms |
8284 KB |
Output is correct |
| 13 |
Correct |
83 ms |
7288 KB |
Output is correct |
| 14 |
Correct |
66 ms |
6212 KB |
Output is correct |
| 15 |
Correct |
97 ms |
8568 KB |
Output is correct |
| 16 |
Correct |
132 ms |
7952 KB |
Output is correct |
| 17 |
Correct |
92 ms |
8056 KB |
Output is correct |
| 18 |
Correct |
118 ms |
8004 KB |
Output is correct |
| 19 |
Correct |
137 ms |
9252 KB |
Output is correct |
| 20 |
Correct |
268 ms |
12352 KB |
Output is correct |
| 21 |
Correct |
151 ms |
11652 KB |
Output is correct |
| 22 |
Correct |
125 ms |
10156 KB |
Output is correct |
| 23 |
Correct |
125 ms |
10336 KB |
Output is correct |
| 24 |
Correct |
129 ms |
11384 KB |
Output is correct |
| 25 |
Correct |
125 ms |
10872 KB |
Output is correct |
| 26 |
Correct |
107 ms |
9208 KB |
Output is correct |
| 27 |
Correct |
140 ms |
11640 KB |
Output is correct |
| 28 |
Correct |
170 ms |
11640 KB |
Output is correct |
| 29 |
Correct |
229 ms |
11640 KB |
Output is correct |
| 30 |
Correct |
298 ms |
13432 KB |
Output is correct |
| 31 |
Correct |
186 ms |
13432 KB |
Output is correct |
| 32 |
Correct |
161 ms |
11512 KB |
Output is correct |
| 33 |
Correct |
127 ms |
10772 KB |
Output is correct |
| 34 |
Correct |
211 ms |
12412 KB |
Output is correct |
| 35 |
Correct |
150 ms |
12076 KB |
Output is correct |
| 36 |
Correct |
176 ms |
12472 KB |
Output is correct |
| 37 |
Correct |
161 ms |
12508 KB |
Output is correct |
| 38 |
Correct |
209 ms |
13808 KB |
Output is correct |
| 39 |
Correct |
251 ms |
13812 KB |
Output is correct |
| 40 |
Correct |
301 ms |
15096 KB |
Output is correct |
| 41 |
Correct |
419 ms |
17144 KB |
Output is correct |
