#include "bits/stdc++.h"
using namespace std;
#define gc getchar_unlocked
#define pb push_back
#define debug(args...) fprintf(stderr,args)
#define FOR(i,a,b) for(int i = a; i <= b; ++i)
#define REP(i,a,b) for(int i = a; i >= b; --i)
typedef long long ll;
typedef pair<int,int>pii;
const int maxn = 1e5 + 10;
int n, m;
struct dsu{
vector<int>par;
void init(){
par.resize(n+1);
FOR(i,1,n)
par[i] = i;
}
int root(int v){
return par[v] = (par[v] == v ? v : root(par[v]));
}
void merge(int x, int y){
x = root(x);
y = root(y);
if(x == y) return;
par[y] = x;
}
void end(){
par.clear();
par.shrink_to_fit();
}
} T[2];
vector<pii>adj[maxn];
static int cnt, cur;
vector<int>h, low;
inline void dfs(int v, int par){
low[v] = h[v] = ++cur;
for(int i = 0; i < adj[v].size(); ++i){
int u = adj[v][i].first;
int e = adj[v][i].second;
if(e == par) continue;
if(h[u] == -1){
dfs(u,e);
low[v] = min(low[v],low[u]);
if(low[u] > h[v]) printf("%d %d\n",u,v);
}
else low[v] = min(low[v],h[u]);
}
}
inline void tarjan(){
h.resize(n+1);
low.resize(n+1);
FOR(i,1,n) h[i] = -1;
FOR(i,1,n)
if(h[i] == -1)
dfs(i,-1);
}
void read (int &x)
{
register int c = gc();
x = 0;
for(;((c<'0'||c>'9')&&c!='-');c=gc());
for(;c>='0'&&c<='9';c=gc())x=(x<<1)+(x<<3)+c-'0';
}
int main(){
read(n);
read(m);
T[0].init();
T[1].init();
FOR(i,1,m){
int a, b;
read(a);
read(b);
if(T[0].root(a) != T[0].root(b)){
++cnt;
adj[a].pb(pii(b,cnt));
adj[b].pb(pii(a,cnt));
T[0].merge(a,b);
}
else if(T[1].root(a) != T[1].root(b)){
++cnt;
adj[a].pb(pii(b,cnt));
adj[b].pb(pii(a,cnt));
T[1].merge(a,b);
}
}
T[0].end();
T[1].end();
tarjan();
return 0;
}
Compilation message
pipes.cpp: In function 'void dfs(int, int)':
pipes.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0; i < adj[v].size(); ++i){
~~^~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
2688 KB |
Output is correct |
2 |
Correct |
3 ms |
2688 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
3200 KB |
Output is correct |
2 |
Correct |
6 ms |
3072 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
31 ms |
3064 KB |
Output is correct |
2 |
Correct |
29 ms |
2948 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
48 ms |
3628 KB |
Output is correct |
2 |
Correct |
54 ms |
3328 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
96 ms |
5104 KB |
Output is correct |
2 |
Correct |
100 ms |
4700 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
180 ms |
9756 KB |
Output is correct |
2 |
Correct |
165 ms |
7696 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
277 ms |
10896 KB |
Output is correct |
2 |
Correct |
251 ms |
8136 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
361 ms |
12800 KB |
Output is correct |
2 |
Correct |
356 ms |
10048 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
399 ms |
12824 KB |
Output is correct |
2 |
Correct |
391 ms |
9972 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
486 ms |
12308 KB |
Output is correct |
2 |
Correct |
495 ms |
9652 KB |
Output is correct |