#include <algorithm>
#include <cstdio>
#include <map>
#include <memory.h>
#include <vector>
using namespace std;
int N, M;
int Lv[111111], C;
int Lo[111111];
int Chk[111111];
int P[111111];
vector<vector<int> > L;
void DFS(int i, int PP)
{
if (Lv[i] == 0) Lv[i] = Lo[i] = ++C;
for (int j = 0; j < L[i].size(); j++) {
if (PP == L[i][j]) continue;
if (Lv[L[i][j]] == 0) {
P[L[i][j]] = i;
DFS(L[i][j], i);
Lo[i] = min(Lo[i], Lo[L[i][j]]);
if (Lv[i] < Lo[L[i][j]]) Chk[L[i][j]] = true;
} else Lo[i] = min(Lo[i], Lv[L[i][j]]);
}
}
int main(void)
{
scanf("%d%d", &N, &M);
L.resize(N + 1);
for (int i = 1; i <= M; i++) {
int u, v;
scanf("%d%d", &u, &v);
L[u].push_back(v);
L[v].push_back(u);
}
DFS(1, 0);
bool Ans = true;
for (int i = 1; i <= N; i++) {
if (!Ans) break;
int CC = 0;
for (int j = 0; j < L[i].size(); j++) {
if (i == P[L[i][j]] && Chk[L[i][j]]) continue;
if (L[i][j] == P[i] && Chk[i]) continue;
CC++;
}
if (!(CC == 0 || CC == 2)) Ans = false;
}
printf("%s\n", Ans ? "Cactus" : "Not cactus");
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
2980 KB |
Output is correct |
| 2 |
Correct |
0 ms |
2980 KB |
Output is correct |
| 3 |
Correct |
0 ms |
3128 KB |
Output is correct |
| 4 |
Correct |
0 ms |
3140 KB |
Output is correct |
| 5 |
Correct |
0 ms |
3112 KB |
Output is correct |
| 6 |
Correct |
0 ms |
3244 KB |
Output is correct |
| 7 |
Correct |
0 ms |
3244 KB |
Output is correct |
| 8 |
Correct |
0 ms |
3112 KB |
Output is correct |
| 9 |
Correct |
0 ms |
3244 KB |
Output is correct |
| 10 |
Correct |
48 ms |
7776 KB |
Output is correct |
| 11 |
Correct |
32 ms |
7352 KB |
Output is correct |
| 12 |
Correct |
36 ms |
10120 KB |
Output is correct |
| 13 |
Correct |
44 ms |
8948 KB |
Output is correct |
| 14 |
Correct |
56 ms |
8576 KB |
Output is correct |
| 15 |
Correct |
60 ms |
11668 KB |
Output is correct |
| 16 |
Correct |
40 ms |
8868 KB |
Output is correct |
| 17 |
Correct |
40 ms |
10232 KB |
Output is correct |
| 18 |
Correct |
64 ms |
13780 KB |
Output is correct |
| 19 |
Correct |
76 ms |
15104 KB |
Output is correct |
| 20 |
Correct |
36 ms |
9312 KB |
Output is correct |
| 21 |
Correct |
60 ms |
9024 KB |
Output is correct |
| 22 |
Correct |
52 ms |
12352 KB |
Output is correct |
| 23 |
Correct |
0 ms |
2980 KB |
Output is correct |
| 24 |
Correct |
0 ms |
2980 KB |
Output is correct |
| 25 |
Correct |
4 ms |
3944 KB |
Output is correct |
| 26 |
Correct |
52 ms |
7836 KB |
Output is correct |
| 27 |
Correct |
20 ms |
4920 KB |
Output is correct |
| 28 |
Correct |
48 ms |
7180 KB |
Output is correct |
| 29 |
Correct |
48 ms |
7180 KB |
Output is correct |
| 30 |
Correct |
52 ms |
7312 KB |
Output is correct |
| 31 |
Correct |
48 ms |
7180 KB |
Output is correct |
| 32 |
Correct |
56 ms |
7836 KB |
Output is correct |
| 33 |
Correct |
60 ms |
7836 KB |
Output is correct |
| 34 |
Correct |
52 ms |
7836 KB |
Output is correct |
