| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 146276 |
2019-08-23T09:26:50 Z |
evpipis |
Pipes (CEOI15_pipes) |
C++11 |
|
5000 ms |
46360 KB |
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define mp make_pair
typedef pair<int, int> ii;
const int len = 1e5+5;
int vis[len], sum[len], n, m;
vector<ii> adj[len];
vector<int> lca[len];
struct dsu{
int anc[len], sz[len], low[len];
void init(){
for (int i = 1; i <= n; i++)
anc[i] = i, sz[i] = 1, low[i] = i;
}
int fin(int i){
if (anc[i] == i) return i;
return anc[i] = fin(anc[i]);
}
void join(int i, int j){
i = fin(i), j = fin(j);
if (i == j) return;
if (sz[i] > sz[j])
sz[i] += sz[j], anc[j] = i;
else
sz[j] += sz[i], anc[i] = j;
low[j] = low[i];
}
};
dsu gen, loc;
void fix(int u){
vis[u] = 1;
for (int j = 0; j < lca[u].size(); j++){
int v = lca[u][j];
if (vis[v]){
sum[u]++;
sum[v]++;
sum[loc.low[loc.fin(v)]] -= 2;
}
}
for (int j = 0; j < adj[u].size(); j++){
ii v = adj[u][j];
if (vis[v.fi])
continue;
fix(v.fi);
loc.join(u, v.fi);
}
}
void dfs(int u){
vis[u] = 1;
for (int j = 0; j < adj[u].size(); j++){
ii v = adj[u][j];
if (!vis[v.fi]){
dfs(v.fi);
sum[u] += sum[v.fi];
if (sum[v.fi])
adj[u][j].se = 0;
}
else{
if (sum[u])
adj[u][j].se = 0;
}
}
}
void print(int u){
vis[u] = 1;
for (int j = 0; j < adj[u].size(); j++){
ii v = adj[u][j];
if (vis[v.fi])
continue;
if (v.se)
printf("%d %d\n", u, v.fi);
print(v.fi);
}
}
int main(){
scanf("%d %d", &n, &m);
gen.init();
while (m > 0){
int k = min(n, m);
m -= k;
//printf("round starts with k = %d\n", k);
loc.init();
for (int i = 1; i <= n; i++){
vis[i] = 0;
sum[i] = 0;
lca[i].clear();
}
for (int i = 0; i < k; i++){
int a, b;
scanf("%d %d", &a, &b);
//printf("edge: a = %d, b = %d\n", a, b);
if (gen.fin(a) != gen.fin(b)){
adj[a].pb(mp(b, 1));
adj[b].pb(mp(a, 1));
gen.join(a, b);
}
else{
lca[a].pb(b);
lca[b].pb(a);
}
}
for (int i = 1; i <= n; i++)
if (!vis[i])
fix(i);
for (int i = 1; i <= n; i++)
vis[i] = 0;
for (int i = 1; i <= n; i++)
if (!vis[i])
dfs(i);
}
for (int i = 1; i <= n; i++)
vis[i] = 0;
for (int i = 1; i <= n; i++)
if (!vis[i])
print(i);
return 0;
}
Compilation message
pipes.cpp: In function 'void fix(int)':
pipes.cpp:45:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (int j = 0; j < lca[u].size(); j++){
~~^~~~~~~~~~~~~~~
pipes.cpp:54:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (int j = 0; j < adj[u].size(); j++){
~~^~~~~~~~~~~~~~~
pipes.cpp: In function 'void dfs(int)':
pipes.cpp:67:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (int j = 0; j < adj[u].size(); j++){
~~^~~~~~~~~~~~~~~
pipes.cpp: In function 'void print(int)':
pipes.cpp:87:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for (int j = 0; j < adj[u].size(); j++){
~~^~~~~~~~~~~~~~~
pipes.cpp: In function 'int main()':
pipes.cpp:99:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~~
pipes.cpp:118:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &a, &b);
~~~~~^~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
6 ms |
5112 KB |
Output is correct |
| 2 |
Correct |
6 ms |
4984 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
13 ms |
5496 KB |
Output is correct |
| 2 |
Correct |
13 ms |
5496 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
274 ms |
5652 KB |
Output is correct |
| 2 |
Correct |
261 ms |
5496 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
524 ms |
6484 KB |
Output is correct |
| 2 |
Correct |
610 ms |
6348 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1051 ms |
8152 KB |
Output is correct |
| 2 |
Runtime error |
784 ms |
21864 KB |
Memory limit exceeded (if you are sure your verdict is not MLE, please contact us) |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1786 ms |
13500 KB |
Output is correct |
| 2 |
Runtime error |
1532 ms |
31628 KB |
Memory limit exceeded (if you are sure your verdict is not MLE, please contact us) |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3098 ms |
15052 KB |
Output is correct |
| 2 |
Runtime error |
2224 ms |
46360 KB |
Memory limit exceeded (if you are sure your verdict is not MLE, please contact us) |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
4153 ms |
17392 KB |
Memory limit exceeded (if you are sure your verdict is not MLE, please contact us) |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
5034 ms |
18604 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
5015 ms |
31112 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
