#include <iostream>
#include <vector>
#define DIM 100002
using namespace std;
int t[DIM],t2[DIM],low[DIM],niv[DIM];
vector <int> L[DIM];
int n,m,i,j,x,y,idx;
inline int get_rad (int x){
int nr = x;
while (t[x] > 0)
x = t[x];
while (t[nr] > 0){
int aux = t[nr];
t[nr] = x;
nr = aux;
}
return x;
}
inline int get_rad2 (int x){
int nr = x;
while (t2[x] > 0)
x = t2[x];
while (t2[nr] > 0){
int aux = t2[nr];
t2[nr] = x;
nr = aux;
}
return x;
}
void dfs(int nod, int tata){
niv[nod] = low[nod] = ++idx;
for(int i=0;i<L[nod].size();++i){
int vecin = L[nod][i];
if (vecin == tata)
continue;
if (niv[vecin])
low[nod] = min (low[nod],niv[vecin]);
else {
dfs (vecin, nod);
low[nod] = min (low[nod],low[vecin]);
if (low[vecin] > niv[nod] && get_rad2(nod) != get_rad2(vecin))
cout<<nod<<" "<<vecin<<"\n";
}}}
int main (){
cin>>n>>m;
for (i=1;i<=n;++i)
t[i] = t2[i] = -1;
for (i=1;i<=m;++i){
cin>>x>>y;
int rx = get_rad (x), ry = get_rad (y);
if (rx != ry){
L[x].push_back(y);
L[y].push_back(x);
if (t[rx] < t[ry]){
t[rx] += t[ry];
t[ry] = rx;
} else {
t[ry] += t[rx];
t[rx] = ry;
}
} else {
/// nodurile se alfa deja in aceeasi multime si toate muchiile
/// de pe drumul de la x la y NU pot fi critice
/// oare merge daca fac din nou paduri pt nodurile astea?
int rx2 = get_rad2 (x), ry2 = get_rad2 (y);
if (rx2 != ry2){
L[x].push_back(y); /// astea ar fi muchiile de intoarcere pt biconexe
L[y].push_back(x);
if (t2[rx2] < t2[ry2]){
t2[rx2] += t2[ry2];
t2[ry2] = rx2;
} else {
t2[ry2] += t2[rx2];
t2[rx2] = ry2;
}}}}
for (i=1;i<=n;++i)
if (!niv[i])
dfs (i,0);
return 0;
}
Compilation message
pipes.cpp: In function 'void dfs(int, int)':
pipes.cpp:32:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<L[nod].size();++i){
~^~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
2680 KB |
Output is correct |
2 |
Correct |
4 ms |
2680 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
3192 KB |
Output is correct |
2 |
Correct |
17 ms |
2936 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
504 ms |
3020 KB |
Output is correct |
2 |
Correct |
492 ms |
2888 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
886 ms |
3700 KB |
Output is correct |
2 |
Correct |
1035 ms |
3296 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1443 ms |
5148 KB |
Output is correct |
2 |
Correct |
1269 ms |
4956 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1926 ms |
9928 KB |
Output is correct |
2 |
Correct |
1646 ms |
7164 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2991 ms |
11064 KB |
Output is correct |
2 |
Correct |
2981 ms |
8716 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3974 ms |
13060 KB |
Output is correct |
2 |
Correct |
3790 ms |
8916 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4964 ms |
13004 KB |
Output is correct |
2 |
Correct |
4663 ms |
8920 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Execution timed out |
5069 ms |
7244 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |