#include <bits/stdc++.h>
#define debug printf
#define ll long long
#define all(x) x.begin(),x.end()
#define sz(x) (int)(x.size() )
const int MAX = 1e5+2 ;
using namespace std ;
struct Event
{
int firstParameter , secondParameter , type ;
Event(int a=0, int b=0, int c=0) : firstParameter(a), secondParameter(b), type(c) {}
bool operator < (Event other ) const
{
if( firstParameter == other.firstParameter ) return type < other.type ;
return firstParameter<other.firstParameter ;
}
} ;
int N , W ;
int dsu[MAX*4] , dist[MAX*4] ;
vector< Event > joinRow, joinCol ;
vector<int> adj[ MAX*4 ] ;
pair<int,int> points[MAX] , Lines[MAX*2] ;
map< pair<int,int> , int > vertices ;
set< pair<int,int> > vis , sweep ;
void add( pair<int,int> p )
{
if( vertices.find(p) != vertices.end() ) return ;
vertices.insert( make_pair(p, sz(vertices)+1 ) ) ;
dsu[ sz(vertices) ] = sz(vertices) ;
joinRow.push_back( Event(p.second,p.first, 1 ) ) ;
joinCol.push_back( Event(p.first, p.second,1 ) ) ;
}
int find(int x)
{
if(x == dsu[x] ) return x;
return dsu[x] = find(dsu[x] ) ;
}
void join(int x, int y )
{
x = find(x);
y = find(y) ;
if( x == y) return ;
if(rand() % 2 ) swap(x,y) ;
dsu[x] = y ;
}
void bfs(int s )
{
vector<int> fila(1,s) ;
int ini = 0 ;
dist[s] = 1 ;
while( ini < sz(fila ) )
{
int x = fila[ini++] ;
for(auto e : adj[x] )
{
if( dist[e] ) continue ;
dist[e] = dist[x] + 1 ;
fila.push_back(e) ;
}
}
}
int main()
{
scanf("%d", &N) ;
for(int i = 0 ; i < N ; i++ )
{
scanf("%d %d", &points[i].first, &points[i].second ) ;
add(make_pair( points[i].first, points[i].second) ) ;
add( make_pair( points[i].first+1, points[i].second) ) ;
add( make_pair( points[i].first, points[i].second+1) ) ;
add( make_pair( points[i].first+1, points[i].second+1) ) ;
}
scanf("%d", &W ) ;
for(int i = 0, A, B ; i < W ; i++ )
{
scanf("%d %d", &A, &B ) ;
--A, --B ;
if( points[A].first == points[B].first )
{
if( points[B].second < points[A].second ) swap(A,B) ;
joinRow.push_back( Event(points[A].second+1,points[A].first+1,0) ) ;
joinRow.push_back( Event(points[B].second+1, points[B].first+1 , -1) ) ;
Lines[i] = make_pair( vertices[make_pair(points[A].first,points[A].second+1)] , vertices[ make_pair(points[A].first+1, points[A].second+1)] ) ;
}
else
{
if( points[B].first < points[A].first ) swap(A,B) ;
joinCol.push_back( Event(points[A].first+1, points[A].second+1, 0) ) ;
joinCol.push_back( Event(points[B].first+1, points[B].second+1, -1) ) ;
Lines[i] = make_pair( vertices[make_pair(points[A].first+1, points[A].second) ], vertices[ make_pair(points[A].first+1, points[A].second+1) ] ) ;
}
}
sort(all(joinRow) ) ;
sort(all(joinCol) ) ;
for(int i= 0 ; i < sz(joinRow) ; )
{
int j = i ;
int firstParameter = joinRow[i].firstParameter ;
while( j < sz(joinRow) && joinRow[j].firstParameter == firstParameter )
{
if( joinRow[j].type != -1 )
sweep.insert( make_pair( joinRow[j].secondParameter,joinRow[j].type ) ) ;
else sweep.erase( sweep.find( make_pair( joinRow[j].secondParameter, 0 ) ) ) ;
j++ ;
}
auto it = sweep.begin() ;
auto nxt = it ; nxt++ ;
while(nxt != sweep.end() )
{
if( it->second == 1 && nxt->second == 1 )
join( vertices[make_pair(it->first, firstParameter) ], vertices[ make_pair(nxt->first, firstParameter) ] ) ;
it++ ;
nxt++ ;
}
for(int g = i ; g < j ; g++ )
{
if( joinRow[g].type != 1 ) continue ;
sweep.erase( sweep.find( make_pair(joinRow[g].secondParameter,1) ) ) ;
}
i = j ;
}
joinRow.clear() ; joinRow.shrink_to_fit() ;
for(int i = 0 ; i < sz(joinCol) ; )
{
int j = i ;
int firstParameter = joinCol[i].firstParameter ;
while( j < sz(joinCol) && joinCol[j].firstParameter == firstParameter )
{
if( joinCol[j].type != -1 )
sweep.insert( make_pair( joinCol[j].secondParameter, joinCol[j].type ) ) ;
else sweep.erase( sweep.find( make_pair( joinCol[j].secondParameter, 0 ) ) ) ;
j++ ;
}
auto it = sweep.begin() ;
auto nxt = it ; nxt++ ;
while( nxt != sweep.end() )
{
if(it->second == 1 && nxt->second == 1 )
join(vertices[make_pair(firstParameter, it->first)], vertices[make_pair(firstParameter, nxt->first) ] ) ;
it++ ;
nxt++ ;
}
for(int g = i ; g < j ; g++ )
{
if( joinCol[g].type != 1 ) continue ;
sweep.erase(sweep.find(make_pair(joinCol[g].secondParameter, 1) ) ) ;
}
i = j ;
}
joinCol.clear() ; joinCol.shrink_to_fit() ;
for(auto e : Lines )
{
adj[ find(e.first) ].push_back( find(e.second) ) ;
adj[ find(e.second) ].push_back( find(e.first) ) ;
}
for(auto e : vertices) vis.insert( make_pair(e.first.first, e.first.second ) ) ;
while( !vis.empty() )
{
int x = vertices[ make_pair( vis.begin()->first, vis.begin()->second) ] ;
vis.erase( vis.begin() ) ;
if( dist[find(x) ] ) continue ;
bfs( find(x) ) ;
}
vector<int> ans ;
for(int i = 0 ; i < W ; i++ )
if( dist[ find(Lines[i].first) ] == dist[ find(Lines[i].second) ] ) ans.push_back(i+1) ;
printf("%d\n", sz(ans ) ) ;
for(auto e :ans ) printf("%d\n", e ) ;
}
Compilation message
flood.cpp: In function 'int main()':
flood.cpp:87:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
87 | scanf("%d", &N) ;
| ~~~~~^~~~~~~~~~
flood.cpp:90:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
90 | scanf("%d %d", &points[i].first, &points[i].second ) ;
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
flood.cpp:98:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
98 | scanf("%d", &W ) ;
| ~~~~~^~~~~~~~~~~
flood.cpp:101:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
101 | scanf("%d %d", &A, &B ) ;
| ~~~~~^~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
11872 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
11872 KB |
Output is correct |
2 |
Correct |
12 ms |
11872 KB |
Output is correct |
3 |
Correct |
14 ms |
11872 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
14 ms |
12000 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
13 ms |
12000 KB |
Output is correct |
2 |
Correct |
16 ms |
12128 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
12000 KB |
Output is correct |
2 |
Correct |
13 ms |
12000 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
13 ms |
12000 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
14 ms |
12164 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
15 ms |
12008 KB |
Output is correct |
2 |
Correct |
16 ms |
12128 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
15 ms |
12000 KB |
Output is correct |
2 |
Correct |
21 ms |
12000 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
216 ms |
23752 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
2085 ms |
38472 KB |
Time limit exceeded |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
2076 ms |
48820 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1283 ms |
62824 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1351 ms |
64368 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |