#include "bits/stdc++.h"
using namespace std;
/** Interface */
inline int readChar();
template <class T = int> inline T readInt();
template <class T> inline void writeInt( T x, char end = 0 );
inline void writeChar( int x );
inline void writeWord( const char *s );
/** Read */
static const int buf_size = 4096;
inline int getChar() {
static char buf[buf_size];
static int len = 0, pos = 0;
if (pos == len)
pos = 0, len = fread(buf, 1, buf_size, stdin);
if (pos == len)
return -1;
return buf[pos++];
}
inline int readChar() {
int c = getChar();
while (c <= 32)
c = getChar();
return c;
}
template <class T>
inline T readInt() {
int s = 1, c = readChar();
T x = 0;
if (c == '-')
s = -1, c = getChar();
while ('0' <= c && c <= '9')
x = x * 10 + c - '0', c = getChar();
return s == 1 ? x : -x;
}
/** Write */
static int write_pos = 0;
static char write_buf[buf_size];
inline void writeChar( int x ) {
if (write_pos == buf_size)
fwrite(write_buf, 1, buf_size, stdout), write_pos = 0;
write_buf[write_pos++] = x;
}
template <class T>
inline void writeInt( T x, char end ) {
if (x < 0)
writeChar('-'), x = -x;
char s[24];
int n = 0;
while (x || !n)
s[n++] = '0' + x % 10, x /= 10;
while (n--)
writeChar(s[n]);
if (end)
writeChar(end);
}
inline void writeWord( const char *s ) {
while (*s)
writeChar(*s++);
}
struct Flusher {
~Flusher() {
if (write_pos)
fwrite(write_buf, 1, write_pos, stdout), write_pos = 0;
}
} flusher;
/** Example */
int *par;
int *bic;
int *subPar;
int *subBic;
vector <int> *g;
int *low, *disc;
bitset <100005> vis;
vector <int> l, r;
int rootPar(int x) {
if(par[x] == x) return x;
return par[x] = rootPar(par[x]);
}
int rootBic(int x) {
if(bic[x] == x) return x;
return bic[x] = rootBic(bic[x]);
}
void joinPar(int x, int y) {
x = rootPar(x);
y = rootPar(y);
if(subPar[x] > subPar[y]) swap(x, y);
if(x != y) {
par[x] = y;
subPar[y] += subPar[x];
}
}
void joinBic(int x, int y) {
x = rootBic(x);
y = rootBic(y);
if(subBic[x] > subBic[y]) swap(x, y);
if(x != y) {
bic[x] = y;
subBic[y] += subBic[x];
}
}
int tym;
void dfs(int x, int parent) {
vis[x] = 1;
low[x] = disc[x] = ++tym;
bool see = false;
for(auto i : g[x]) {
if (!see && i == parent) {
see = true;
continue;
}
if(vis[i] == 0) {
dfs(i, x);
low[x] = min(low[x], low[i]);
if(disc[x] < low[i]) {
l.push_back(x);
r.push_back(i);
}
} else if (vis[i] == 1) {
low[x] = min(low[x], disc[i]);
}
}
}
int main(int argc, char const *argv[])
{
int n, m;
n = readInt();
m = readInt();
par = new int [n + 5];
bic = new int [n + 5];
subPar = new int [n + 5];
subBic = new int [n + 5];
for(int i = 1; i <= n; i++) {
par[i] = i;
bic[i] = i;
subPar[i] = subBic[i] = 1;
}
for(int i = 1; i <= m; i++) {
int p, q;
p = readInt();
q = readInt();
if(rootPar(p) != rootPar(q)) {
joinPar(p, q);
l.push_back(p);
r.push_back(q);
} else if (rootBic(q) != rootBic(p)) {
joinBic(p, q);
l.push_back(p);
r.push_back(q);
}
}
delete par;
delete bic;
delete subPar;
delete subBic;
g = new vector <int> [n + 5];
for(size_t i = 0; i < l.size(); i++) {
g[l[i]].push_back(r[i]);
g[r[i]].push_back(l[i]);
}
l.clear();
r.clear();
low = new int [n + 5];
disc = new int [n + 5];
for(int i = 1; i <= n; i++) {
if(vis[i] == 0) {
dfs(i, 0);
}
}
for(size_t i = 0; i < l.size(); i++) {
printf("%d %d\n", l[i], r[i]);
}
delete low;
delete disc;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
384 KB |
Output is correct |
2 |
Correct |
2 ms |
384 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
896 KB |
Output is correct |
2 |
Correct |
3 ms |
768 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
21 ms |
768 KB |
Output is correct |
2 |
Correct |
22 ms |
640 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
34 ms |
1656 KB |
Output is correct |
2 |
Correct |
39 ms |
1276 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
72 ms |
3480 KB |
Output is correct |
2 |
Correct |
61 ms |
3288 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
117 ms |
9760 KB |
Output is correct |
2 |
Correct |
114 ms |
6948 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
169 ms |
11192 KB |
Output is correct |
2 |
Correct |
158 ms |
8456 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
238 ms |
13796 KB |
Output is correct |
2 |
Correct |
225 ms |
9684 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
293 ms |
13796 KB |
Output is correct |
2 |
Correct |
269 ms |
9684 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
337 ms |
13088 KB |
Output is correct |
2 |
Correct |
323 ms |
10476 KB |
Output is correct |