//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
#define mem(a,v) memset((a), (v), sizeof (a))
#define enl printf("\n")
#define case(t) printf("Case #%d: ", (t))
#define ni(n) scanf("%d", &(n))
#define nl(n) scanf("%I64d", &(n))
#define nai(a, n) for (int i = 0; i < (n); i++) ni(a[i])
#define nal(a, n) for (int i = 0; i < (n); i++) nl(a[i])
#define pri(n) printf("%d\n", (n))
#define prl(n) printf("%I64d\n", (n))
#define pii pair<int, int>
#define pil pair<int, long long>
#define pll pair<long long, long long>
#define vii vector<pii>
#define vil vector<pil>
#define vll vector<pll>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef cc_hash_table<int,int,hash<int>> ht;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> oset;
const double pi = acos(-1);
const int MOD = 1e9 + 7;
const int INF = 1e9 + 7;
const int MAXN = 1e3 + 5;
const int MAXM = 1e5 + 5;
const double eps = 1e-9;
int U[MAXN], V[MAXN], ap[MAXM], mrk[MAXM];
int lo[MAXN], disc[MAXN], ti = 1, inSt[MAXN];
vi adj[MAXN];
void dfs(int u, int p=0) {
lo[u] = disc[u] = ti++;
for (int i: adj[u]) {
int v = U[i]^V[i]^u;
if (!disc[v]) {
dfs(v, u);
lo[u] = min(lo[u], lo[v]);
if (lo[v] > disc[u])
ap[i] = 1;
} else if (v != p)
lo[u] = min(lo[u], disc[v]);
}
}
stack<int> st;
void solve(int u, int root, int d=0, int p=0) {
disc[u] = 1;
bool fl = 0;
//cerr << "current node: " << u << " " << d << " " << p << "\n";
for (int i: adj[u]) {
int v = U[i]^V[i]^u;
if (ap[i] || v == p)
continue;
if (mrk[i] && inSt[v])
return;
if (mrk[i])
continue;
if (disc[v] && (v != root || (v == root && d <= 2))) {
disc[u] = 0;
return;
}
if (v == root && d > 2)
fl = 1;
}
st.push(u);
inSt[u] = 1;
if (fl) {
while (!st.empty()) {
printf("%d ", st.top());
st.pop();
}
printf("\n");
exit(0);
}
random_shuffle(adj[u].begin(), adj[u].end());
for (int i: adj[u]) {
int v = U[i]^V[i]^u;
if (ap[i] || v == p || mrk[i]) continue;
solve(v, root, d+1, u);
mrk[i] = 1;
}
inSt[u] = 0;
st.pop();
}
int deg[MAXN];
int main() {
srand(time(0));
int n, m;
scanf("%d %d", &n, &m);
for (int i = 1; i <= m; i++) {
scanf("%d %d", U+i, V+i);
adj[U[i]].pb(i);
adj[V[i]].pb(i);
deg[U[i]]++, deg[V[i]]++;
}
for (int i= 1; i <= n; i++)
if (deg[i] > 70)
cerr << i << " " << deg[i] << "\n";
for (int i = 1; i <= n; i++)
if (!disc[i])
dfs(i);
//for (int i = 1; i <= m; i++)
// cerr << "edge " << U[i] << " " << V[i] << " stat: " << ap[i] << "\n";
for (int i = 1; i <= n; i++) {
mem(disc, 0);
mem(inSt, 0);
mem(mrk, 0);
//cerr << "check root: " << i << "\n";
solve(i, i);
while (!st.empty())
st.pop();
//cerr << "\n";
}
printf("no\n");
return 0;
}
Compilation message
indcyc.cpp: In function 'int main()':
indcyc.cpp:103:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~~
indcyc.cpp:105:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", U+i, V+i);
~~~~~^~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
760 KB |
Output is correct |
| 2 |
Correct |
2 ms |
808 KB |
Output is correct |
| 3 |
Correct |
3 ms |
760 KB |
Output is correct |
| 4 |
Correct |
2 ms |
760 KB |
Output is correct |
| 5 |
Correct |
2 ms |
376 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
760 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
760 KB |
Output is correct |
| 2 |
Correct |
2 ms |
760 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
760 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
8 ms |
764 KB |
Repeated vertex |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
888 KB |
Wrong answer on graph without induced cycle |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
3 ms |
636 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3 ms |
504 KB |
Time limit exceeded (wall clock) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3 ms |
504 KB |
Time limit exceeded (wall clock) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3 ms |
504 KB |
Time limit exceeded (wall clock) |
| 2 |
Halted |
0 ms |
0 KB |
- |
