#include <bits/stdc++.h>
using namespace std;
int a[300001], b[300001], cmp[600001];
bool cnt[300001], visited[300001];
vector<pair<int, int>> graph[300001];
vector<array<int, 3>> ans;
int find(int A) {
while (A != cmp[A]) A = cmp[A], cmp[A] = cmp[cmp[A]];
return A;
}
void onion(int A, int B) { cmp[find(A)] = find(B); }
bool dfs(int node) {
visited[node] = true;
for (pair<int, int> i : graph[node]) {
if (!visited[i.first] && dfs(i.first)) {
ans.push_back({1, a[i.second], b[i.second]});
swap(a[i.second], b[i.second]);
cnt[node] ^= 1;
}
}
return cnt[node];
}
int main() {
iostream::sync_with_stdio(false);
cin.tie(0);
int n, m;
cin >> n >> m;
for (int i = 0; i < m; i++) {
cin >> a[i] >> b[i];
cnt[a[i]] ^= 1;
graph[a[i]].push_back({b[i], i});
graph[b[i]].push_back({a[i], i});
}
for (int i = 1; i <= n; i++) {
if (!visited[i] && dfs(i)) return cout << -1, 0;
}
memset(cnt, 0, sizeof cnt);
iota(cmp + 1, cmp + 2 * n + 1, 1);
for (int i = 0; i < m; i++) {
cnt[b[i]] ^= 1;
onion(a[i] + n, b[i]);
}
for (int i = 1; i <= n; i++) if (find(1) != find(i)) {
ans.push_back({2, 1, i});
cnt[1] ^= 1;
cnt[i] ^= 1;
onion(1, i);
}
vector<int> odd;
for (int i = 1; i <= n; i++) if (cnt[i]) odd.push_back(i);
for (int i = 0; i < odd.size(); i += 2) ans.push_back({2, odd[i], odd[i + 1]});
cout << ans.size() << '\n';
for (array<int, 3> i : ans) {
cout << i[0] << ' ' << i[1] << ' ' << i[2] << '\n';
}
return 0;
}
Compilation message
main.cpp: In function 'int main()':
main.cpp:57:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
57 | for (int i = 0; i < odd.size(); i += 2) ans.push_back({2, odd[i], odd[i + 1]});
| ~~^~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 2 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 3 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 4 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 5 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 6 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 7 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 8 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 9 |
Correct |
5 ms |
7424 KB |
Output is correct |
| 10 |
Correct |
6 ms |
7680 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 2 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 3 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 4 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 5 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 6 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 7 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 8 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 9 |
Correct |
6 ms |
7424 KB |
Output is correct |
| 10 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 11 |
Correct |
5 ms |
7552 KB |
Output is correct |
| 12 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 13 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 14 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 15 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 16 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 17 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 18 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 19 |
Correct |
6 ms |
7936 KB |
Output is correct |
| 20 |
Correct |
6 ms |
7680 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 2 |
Correct |
5 ms |
7680 KB |
Output is correct |
| 3 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 4 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 5 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 6 |
Correct |
7 ms |
7680 KB |
Output is correct |
| 7 |
Correct |
8 ms |
7680 KB |
Output is correct |
| 8 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 9 |
Correct |
5 ms |
7424 KB |
Output is correct |
| 10 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 11 |
Correct |
6 ms |
7424 KB |
Output is correct |
| 12 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 13 |
Correct |
6 ms |
7936 KB |
Output is correct |
| 14 |
Correct |
7 ms |
7808 KB |
Output is correct |
| 15 |
Correct |
8 ms |
7808 KB |
Output is correct |
| 16 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 17 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 18 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 19 |
Correct |
6 ms |
7936 KB |
Output is correct |
| 20 |
Correct |
6 ms |
7680 KB |
Output is correct |
| 21 |
Correct |
326 ms |
28912 KB |
Output is correct |
| 22 |
Correct |
362 ms |
39556 KB |
Output is correct |
| 23 |
Correct |
161 ms |
26712 KB |
Output is correct |
| 24 |
Correct |
52 ms |
16632 KB |
Output is correct |
| 25 |
Correct |
63 ms |
18168 KB |
Output is correct |
| 26 |
Correct |
221 ms |
31976 KB |
Output is correct |
| 27 |
Correct |
95 ms |
20984 KB |
Output is correct |
| 28 |
Correct |
81 ms |
21240 KB |
Output is correct |
| 29 |
Correct |
233 ms |
42960 KB |
Output is correct |
| 30 |
Correct |
212 ms |
38224 KB |
Output is correct |
| 31 |
Correct |
74 ms |
16888 KB |
Output is correct |
| 32 |
Correct |
250 ms |
39260 KB |
Output is correct |
| 33 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 34 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 35 |
Correct |
291 ms |
28784 KB |
Output is correct |
| 36 |
Correct |
73 ms |
17016 KB |
Output is correct |
| 37 |
Correct |
6 ms |
7808 KB |
Output is correct |
| 38 |
Correct |
6 ms |
7936 KB |
Output is correct |
