#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
int n,m;
vector<vector<unsigned short>> muchii;
vector<vector<short>> bits;
bool use[100005];
int par[100005];
int niv[100005],nivmin[100005];
void add(int a,int b)
{
if(muchii[a].size()%15==0)
{
short x=0;
bits[a].push_back(x);
}
int val=bits[a].back();
if((b>>16)&1)
{
int nrbit=muchii[a].size()%15;
val+=(1<<nrbit);
bits[a].back()=val;
b-=(1<<16);
}
muchii[a].push_back(b);
}
int getnum(int a,int poz)
{
int x=muchii[a][poz];
int grup=poz/15;
int bit=poz%15;
if((bits[a][grup]>>bit&1))
x+=(1<<16);
return x;
}
void dfs(int nod)
{
use[nod]=1;
nivmin[nod]=niv[nod];
for(int i=0;i<muchii[nod].size();i++)
{
int node=getnum(nod,i);
if(node==par[nod])
continue;
if(!use[node])
{
par[node]=nod;
niv[node]=niv[nod]+1;
dfs(node);
nivmin[nod]=min(nivmin[nod],nivmin[node]);
}
else
nivmin[nod]=min(nivmin[nod],niv[node]);
}
int cnt=0;
if(nivmin[nod]==niv[nod]&&par[nod]!=0)
{
for(int i=0;i<muchii[nod].size();i++)
{
int x=getnum(nod,i);
if(x==par[nod])
cnt++;
}
if(cnt==1)
cout<<par[nod]<<' '<<nod<<'\n';
}
}
int main()
{
cin>>n>>m;
muchii.resize(n+1);
bits.resize(n+1);
for(int i=1;i<=m;i++)
{
int a,b;
cin>>a>>b;
add(b,a);
add(a,b);
}
for(int i=1;i<=n;i++)
if(!use[i])
{
niv[i]=1;
dfs(i);
}
return 0;
}
Compilation message
pipes.cpp: In function 'void dfs(int)':
pipes.cpp:41:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<short unsigned int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
41 | for(int i=0;i<muchii[nod].size();i++)
| ~^~~~~~~~~~~~~~~~~~~
pipes.cpp:59:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<short unsigned int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
59 | for(int i=0;i<muchii[nod].size();i++)
| ~^~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
308 KB |
Output is correct |
2 |
Correct |
1 ms |
212 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
1236 KB |
Output is correct |
2 |
Correct |
8 ms |
876 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
273 ms |
6920 KB |
Output is correct |
2 |
Correct |
311 ms |
6496 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
502 ms |
9760 KB |
Output is correct |
2 |
Correct |
582 ms |
11624 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
865 ms |
17432 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
1295 ms |
28788 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
2088 ms |
40768 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
2885 ms |
61644 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
3636 ms |
65536 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
4450 ms |
65536 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |