//#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
using namespace std;
typedef long long llo;
#define mp make_pair
#define pb push_back
#define a first
#define b second
//#define endl '\n'
int n,k;
int aa[300001];
int bb[300001];
int it[300001];
set<int> pre[300001];
vector<int> adj[300001];
vector<int> adj2[300001];
int vis[300001];
void add(int i,int j){
adj[2*i+1].pb(2*j);
adj[2*j+1].pb(2*i);
/*cout<<2*i+1<<"<<"<<2*j<<endl;
cout<<2*j+1<<"<<"<<2*i<<endl;
cout<<endl;*/
}
void add2(int i,int j){
adj[2*i].pb(2*j+1);
adj[2*j].pb(2*i+1);
/*cout<<2*i+1<<"<<"<<2*j<<endl;
cout<<2*j+1<<"<<"<<2*i<<endl;
cout<<endl;*/
}
vector<int> ord;
void dfs(int no){
vis[no]=1;
pair<int,int> cur2;
cur2.b=(no%2);
cur2.a=no/2;
int ind=cur2.a/2;
if(cur2.b==1){
if(cur2.a%2==0){
pre[aa[ind]].erase(cur2.a);
}
else{
pre[bb[ind]].erase(cur2.a);
}
}
for(auto j:adj[no]){
if(vis[j]==0){
dfs(j);
}
}
if(cur2.b==0){
if(cur2.a%2==0){
while(pre[aa[ind]].size()){
int st=0;
for(auto j:pre[aa[ind]]){
if(j!=cur2.a){
//cout<<no<<":"<<j*2+1<<endl;
dfs(j*2+1);
st=1;
break;
}
}
if(st==0){
break;
}
}
}
else{
while(pre[bb[ind]].size()){
int st=0;
for(auto j:pre[bb[ind]]){
if(j!=cur2.a){
// cout<<no<<":"<<j*2+1<<endl;
dfs(j*2+1);
st=1;
break;
}
}
if(st==0){
break;
}
}
}
}
ord.pb(no);
}
int cur=0;
void dfs2(int no){
vis[no]=cur;
pair<int,int> cur;
cur.b=(no%2);
cur.a=no/2;
int ind=cur.a/2;
if(cur.b==0){
if(cur.a%2==0){
pre[aa[ind]].erase(cur.a);
}
else{
pre[bb[ind]].erase(cur.a);
}
}
for(auto j:adj2[no]){
if(vis[j]==0){
dfs2(j);
}
}
if(cur.b==1){
if(cur.a%2==0){
while(pre[aa[ind]].size()){
int st=0;
for(auto j:pre[aa[ind]]){
if(j!=cur.a){
dfs2(j*2);
st=1;
break;
}
}
if(st==0){
break;
}
}
}
else{
while(pre[bb[ind]].size()){
int st=0;
for(auto j:pre[bb[ind]]){
if(j!=cur.a){
dfs2(j*2);
st=1;
break;
}
}
if(st==0){
break;
}
}
}
}
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>n>>k;
for(int i=0;i<2*n;i++){
cin>>aa[i]>>bb[i]>>it[i];
aa[i]--;
bb[i]--;
bb[i]+=n;
pre[aa[i]].insert(2*i);
pre[bb[i]].insert(2*i+1);
add(i*2,i*2+1);
}
/*for(int i=0;i<2*n;i++){
for(auto jj:pre[aa[i]]){
int j=jj/2;
if(j!=i){
// cout<<i<<":"<<j<<endl;
//not(j*2) or not(i*2)
// add2(i*2,j*2);
// continue;
adj[(j*2)*2].pb(2*(2*i)+1);
adj[(i*2)*2].pb((j*2)*2+1);
}
}
for(auto jj:pre[bb[i]]){
int j=jj/2;
if(j!=i){
//cout<<i<<","<<j<<endl;
// add2(i*2+1,j*2+1);
//continue;
adj[(j*2+1)*2].pb(2*(2*i+1)+1);
adj[(i*2+1)*2].pb((j*2+1)*2+1);
}
}
}
*/
for(int i=0;i<8*n;i++){
for(auto j:adj[i]){
adj2[j].pb(i);
//cout<<j<<".."<<i<<endl;
}
}
for(int i=0;i<8*n;i++){
if(vis[i]==0){
dfs(i);
}
}
reverse(ord.begin(),ord.end());
/*for(auto i:ord){
cout<<i<<":";
}
cout<<endl;*/
for(int i=0;i<2*n;i++){
pre[aa[i]].insert(i*2);
pre[bb[i]].insert(i*2+1);
}
for(int j=0;j<8*n;j++){
vis[j]=0;
}
for(auto j:ord){
if(vis[j]==0){
cur++;
dfs2(j);
}
}
int st=1;
for(int i=0;i<8*n;i+=2){
if(vis[i]==vis[i+1]){
st=0;
}
}
/*for(int i=0;i<8*n;i++){
cout<<vis[i]<<",";
}
cout<<endl;*/
if(st){
cout<<"YES"<<endl;
}
else{
cout<<"NO"<<endl;
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
20 ms |
28524 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
20 ms |
28524 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
49 ms |
34412 KB |
Output is correct |
2 |
Correct |
63 ms |
34412 KB |
Output is correct |
3 |
Correct |
50 ms |
34560 KB |
Output is correct |
4 |
Correct |
60 ms |
34540 KB |
Output is correct |
5 |
Correct |
49 ms |
34540 KB |
Output is correct |
6 |
Correct |
60 ms |
34412 KB |
Output is correct |
7 |
Correct |
49 ms |
34412 KB |
Output is correct |
8 |
Correct |
59 ms |
34412 KB |
Output is correct |
9 |
Correct |
53 ms |
34412 KB |
Output is correct |
10 |
Correct |
62 ms |
34412 KB |
Output is correct |
11 |
Correct |
50 ms |
34412 KB |
Output is correct |
12 |
Correct |
57 ms |
34412 KB |
Output is correct |
13 |
Correct |
53 ms |
34412 KB |
Output is correct |
14 |
Correct |
52 ms |
34412 KB |
Output is correct |
15 |
Correct |
60 ms |
34412 KB |
Output is correct |
16 |
Correct |
50 ms |
34412 KB |
Output is correct |
17 |
Correct |
58 ms |
34412 KB |
Output is correct |
18 |
Correct |
51 ms |
34300 KB |
Output is correct |
19 |
Correct |
60 ms |
34412 KB |
Output is correct |
20 |
Correct |
61 ms |
34412 KB |
Output is correct |
21 |
Correct |
63 ms |
36076 KB |
Output is correct |
22 |
Correct |
54 ms |
34412 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
20 ms |
28524 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |