#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
#define ld long double
// 217
// 44
using namespace std;
const int MAXN = (int) 2e5;
vector <int> g[MAXN + 1];
int dst[MAXN + 1][2];
inline void bfs(int nod, bool t) {
queue <int> Q;
dst[nod][t] = 1;
Q.push(nod);
while(Q.size()) {
nod = Q.front();
Q.pop();
for(auto it : g[nod]) {
if(dst[it][t] == 0) {
dst[it][t] = dst[nod][t] + 1;
Q.push(it);
}
}
}
}
int dfs(int nod) {
for(auto it : g[nod]) {
if(dst[nod][0] == dst[it][0] + 1 && dst[nod][1] == dst[it][1] + 1) {
return dfs(it) + 1;
}
}
return 0;
}
int main() {
//ifstream cin("A.in");
//ofstream cout("A.out");
int i, n, m, s, d, a, b;
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
cin >> n >> m;
cin >> s >> d >> a >> b;
for(i = 1; i <= m; i++) {
int x, y;
cin >> x >> y;
g[x].push_back(y);
g[y].push_back(x);
}
bfs(a, 0);
bfs(b, 1);
if(dst[s][0] != dst[d][0] || dst[s][1] != dst[d][1]) {
cout << max(-1, min(dst[d][0] - dst[s][0], dst[d][1] - dst[s][1]));
return 0;
}
int cnt_s = dfs(s), cnt_d = dfs(d);
int ans = -1;
if(dst[s][0] <= dst[d][0]) {
if(cnt_s + dst[d][0] - dst[s][0] >= cnt_d) {
ans = max(ans, dst[d][0] - dst[s][0]);
}
else {
ans = max(ans, dst[d][0] - dst[s][0] - 1);
}
}
cout << ans;
//cin.close();
//cout.close();
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
4984 KB |
Output is correct |
2 |
Correct |
5 ms |
4984 KB |
Output is correct |
3 |
Correct |
6 ms |
4988 KB |
Output is correct |
4 |
Incorrect |
5 ms |
4984 KB |
Output isn't correct |
5 |
Incorrect |
6 ms |
4984 KB |
Output isn't correct |
6 |
Correct |
6 ms |
5112 KB |
Output is correct |
7 |
Correct |
6 ms |
4984 KB |
Output is correct |
8 |
Incorrect |
5 ms |
4984 KB |
Output isn't correct |
9 |
Correct |
5 ms |
4984 KB |
Output is correct |
10 |
Correct |
5 ms |
5112 KB |
Output is correct |
11 |
Correct |
5 ms |
5156 KB |
Output is correct |
12 |
Incorrect |
5 ms |
5212 KB |
Output isn't correct |
13 |
Correct |
5 ms |
5112 KB |
Output is correct |
14 |
Incorrect |
5 ms |
5004 KB |
Output isn't correct |
15 |
Correct |
5 ms |
4984 KB |
Output is correct |
16 |
Incorrect |
5 ms |
5092 KB |
Output isn't correct |
17 |
Incorrect |
5 ms |
5112 KB |
Output isn't correct |
18 |
Incorrect |
5 ms |
5112 KB |
Output isn't correct |
19 |
Correct |
5 ms |
5112 KB |
Output is correct |
20 |
Correct |
5 ms |
5112 KB |
Output is correct |
21 |
Correct |
5 ms |
4984 KB |
Output is correct |
22 |
Correct |
5 ms |
5116 KB |
Output is correct |
23 |
Correct |
5 ms |
5112 KB |
Output is correct |
24 |
Incorrect |
5 ms |
5128 KB |
Output isn't correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
21 ms |
6924 KB |
Output is correct |
2 |
Incorrect |
26 ms |
7544 KB |
Output isn't correct |
3 |
Correct |
22 ms |
6904 KB |
Output is correct |
4 |
Incorrect |
31 ms |
7672 KB |
Output isn't correct |
5 |
Correct |
26 ms |
6776 KB |
Output is correct |
6 |
Correct |
27 ms |
7032 KB |
Output is correct |
7 |
Correct |
26 ms |
7252 KB |
Output is correct |
8 |
Correct |
29 ms |
7160 KB |
Output is correct |
9 |
Incorrect |
43 ms |
7672 KB |
Output isn't correct |
10 |
Correct |
145 ms |
11960 KB |
Output is correct |
11 |
Incorrect |
43 ms |
8872 KB |
Output isn't correct |
12 |
Correct |
59 ms |
9768 KB |
Output is correct |
13 |
Incorrect |
45 ms |
9080 KB |
Output isn't correct |
14 |
Correct |
38 ms |
8440 KB |
Output is correct |
15 |
Correct |
52 ms |
9848 KB |
Output is correct |
16 |
Correct |
54 ms |
10104 KB |
Output is correct |
17 |
Correct |
58 ms |
9592 KB |
Output is correct |
18 |
Incorrect |
61 ms |
9624 KB |
Output isn't correct |
19 |
Correct |
107 ms |
10744 KB |
Output is correct |
20 |
Incorrect |
190 ms |
13560 KB |
Output isn't correct |
21 |
Incorrect |
85 ms |
11620 KB |
Output isn't correct |
22 |
Correct |
86 ms |
10764 KB |
Output is correct |
23 |
Correct |
79 ms |
11512 KB |
Output is correct |
24 |
Correct |
98 ms |
11388 KB |
Output is correct |
25 |
Incorrect |
101 ms |
11128 KB |
Output isn't correct |
26 |
Correct |
80 ms |
10744 KB |
Output is correct |
27 |
Correct |
109 ms |
11512 KB |
Output is correct |
28 |
Correct |
132 ms |
11704 KB |
Output is correct |
29 |
Correct |
145 ms |
12256 KB |
Output is correct |
30 |
Incorrect |
220 ms |
14216 KB |
Output isn't correct |
31 |
Incorrect |
129 ms |
12536 KB |
Output isn't correct |
32 |
Correct |
135 ms |
11548 KB |
Output is correct |
33 |
Correct |
96 ms |
11688 KB |
Output is correct |
34 |
Incorrect |
152 ms |
12124 KB |
Output isn't correct |
35 |
Incorrect |
115 ms |
11740 KB |
Output isn't correct |
36 |
Incorrect |
106 ms |
12024 KB |
Output isn't correct |
37 |
Correct |
138 ms |
12908 KB |
Output is correct |
38 |
Correct |
145 ms |
12664 KB |
Output is correct |
39 |
Correct |
170 ms |
12792 KB |
Output is correct |
40 |
Incorrect |
213 ms |
14456 KB |
Output isn't correct |
41 |
Correct |
294 ms |
16540 KB |
Output is correct |