#include <bits/stdc++.h>
using namespace std;
typedef long long lint;
typedef pair<int, int> pi;
struct disj{
int pa[600005];
void init(int n){
iota(pa, pa + n + 1, 0);
}
int find(int x){
return pa[x] = (pa[x] == x ? x : find(pa[x]));
}
bool uni(int p, int q){
p = find(p);
q = find(q);
if(p == q) return 0;
pa[q] = p; return 1;
}
}disj;
int n, m, cnt[300005], sum;
int s[300005], e[300005], vis[300005];
vector<pi> gph[300005];
vector<int> v;
vector<tuple<int, int, int>> ans;
int dfs(int x, int p){
vis[x] = 1;
int ret = cnt[x];
for(auto &i : gph[x]){
if(i.second != p && dfs(i.second, x)){
ans.emplace_back(1, s[i.first], e[i.first]);
swap(s[i.first], e[i.first]);
ret ^= 1;
}
}
return ret;
}
int main(){
scanf("%d %d",&n,&m);
disj.init(n);
for(int i=0; i<m; i++){
scanf("%d %d",&s[i],&e[i]);
cnt[s[i]] ^= 1;
if(disj.uni(s[i], e[i])){
gph[s[i]].push_back(pi(i, e[i]));
gph[e[i]].push_back(pi(i, s[i]));
}
}
for(int i=1; i<=n; i++){
if(!vis[i]){
if(dfs(i, -1)){
puts("-1");
return 0;
}
}
}
memset(cnt, 0, sizeof(cnt));
disj.init(2*n);
for(int i=0; i<m; i++){
disj.uni(s[i] + n, e[i]);
cnt[e[i]] ^= 1;
}
for(int i=2; i<=n; i++){
if(disj.uni(1, i)){
ans.emplace_back(2, 1, i);
cnt[1] ^= 1;
cnt[i] ^= 1;
}
}
v.clear();
for(int i=1; i<=n; i++) if(cnt[i]) v.push_back(i);
for(int i=0; i<v.size(); i+=2) ans.emplace_back(2, v[i], v[i+1]);
cout << 3*ans.size() << endl;
for(auto &i : ans) printf("%d %d %d\n", get<0>(i), get<1>(i), get<2>(i));
for(auto &i : ans) printf("%d %d %d\n", get<0>(i), get<1>(i), get<2>(i));
for(auto &i : ans) printf("%d %d %d\n", get<0>(i), get<1>(i), get<2>(i));
}
Compilation message
main.cpp: In function 'int main()':
main.cpp:75:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
75 | for(int i=0; i<v.size(); i+=2) ans.emplace_back(2, v[i], v[i+1]);
| ~^~~~~~~~~
main.cpp:42:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
42 | scanf("%d %d",&n,&m);
| ~~~~~^~~~~~~~~~~~~~~
main.cpp:45:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
45 | scanf("%d %d",&s[i],&e[i]);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
8 ms |
8576 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
8 ms |
8576 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
7 ms |
8576 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
