#include <bits/stdc++.h>
#define ll long long
#define db long double
#define N 100005
#define II pair <int,int>
#define III pair <ll,II>
#define IV pair <vector <int>,vector <int> >
#define fst first
#define snd second
#define BIT(x,i) ((x>>i)&1)
#define Log(x) (31-__builtin_clz((int)x))
#define LogLL(x) (63-__builtin_clzll((ll)x))
#define pi acos(-1)
#define to_radian(x) (x*pi/180.0)
#define to_degree(x) (x*180.0/pi)
using namespace std;
struct point { int x,y; } a[N];
II e[2*N];
int U[N],D[N],L[N],R[N],n,m,i,u,v,mx[N],f[4*N];
bool visited[N];
vector <int> adj[4*N];
int main()
{
// freopen("flood.inp","r",stdin);
// freopen("flood.out","w",stdout);
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin>>n;
for(i=1;i<=n;i++) cin>>a[i].x>>a[i].y;
cin>>m;
for(i=1;i<=m;i++)
{
cin>>u>>v;
if(a[u].x>a[v].x || (a[u].x==a[v].x && a[u].y>a[v].y)) swap(u,v);
e[i]={ u,v };
if(a[u].x==a[v].x) U[u]=D[v]=i; else R[u]=L[v]=i;
}
//////////////////////////////////////////////////////////////////////////////////////
auto BFS_point=[&](int u)
{
queue <int> q;
vector <int> vec;
int ma=0;
q.push(u); visited[u]=1;
while(q.size()>0)
{
int u=q.front(); q.pop();
vec.push_back(u);
ma=max(ma,a[u].x);
auto consider=[&](int x)
{
if(x==0) return ;
int v=(e[x].fst==u ? e[x].snd : e[x].fst);
if(visited[v]) return ;
q.push(v); visited[v]=1;
};
consider(U[u]);
consider(D[u]);
consider(L[u]);
consider(R[u]);
}
for(int u:vec) mx[u]=ma;
};
for(u=1;u<=n;u++)
if(visited[u]==0) BFS_point(u);
///////////////////////////////////////////////////////////////////////////////
for(u=1;u<=n;u++)
{
auto consider=[&](II a,II b)
{
int u=a.fst+m*(a.snd==1 || a.snd==4),v=b.fst+m*(b.snd==2 || b.snd==3);
adj[u].push_back(v); adj[v].push_back(u);
};
vector <II> vec;
if(U[u]>0) vec.push_back({ U[u],1 });
if(R[u]>0) vec.push_back({ R[u],2 });
if(D[u]>0) vec.push_back({ D[u],3 });
if(L[u]>0) vec.push_back({ L[u],4 });
if(vec.size()==0) continue;
if(vec.size()==1)
{
int u=vec[0].fst,v=vec[0].fst+m;
adj[u].push_back(v); adj[v].push_back(u);
}
else
{
for(i=1;i<vec.size();i++) consider(vec[i-1],vec[i]);
consider(vec.back(),vec[0]);
}
}
set <II> s;
memset(f,63,sizeof(f));
for(i=1;i<=m;i++)
{
int u=e[i].fst,v=e[i].snd;
if(a[v].x==mx[v])
{
if(a[u].x==a[v].x)
s.insert({ 0,i+m }),f[i+m]=0;
else if(U[v]==0 && D[v]==0)
s.insert({ 0,i }),s.insert({ 0,i+m }),f[i]=f[i+m]=0;
}
}
while(s.size()>0)
{
int u=s.begin()->snd,v; s.erase(s.begin());
for(int v:adj[u])
if(f[v]>f[u])
{
s.erase({ f[v],v });
f[v]=f[u];
s.insert({ f[v],v });
}
if(u<=m) v=u+m; else v=u-m;
if(f[v]>f[u]+1)
{
s.erase({ f[v],v });
f[v]=f[u]+1;
s.insert({ f[v],v });
}
}
int res=0;
for(i=1;i<=m;i++) res+=(f[i]==f[i+m]);
cout<<res<<'\n';
for(i=1;i<=m;i++) if(f[i]==f[i+m]) cout<<i<<'\n';
}
Compilation message
flood.cpp: In function 'int main()':
flood.cpp:92:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
92 | for(i=1;i<vec.size();i++) consider(vec[i-1],vec[i]);
| ~^~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
14952 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
14940 KB |
Output is correct |
2 |
Correct |
3 ms |
14940 KB |
Output is correct |
3 |
Correct |
3 ms |
14940 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
15092 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
14940 KB |
Output is correct |
2 |
Correct |
3 ms |
14940 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
14940 KB |
Output is correct |
2 |
Correct |
3 ms |
14980 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
14940 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
14940 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
15096 KB |
Output is correct |
2 |
Correct |
3 ms |
14996 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
14940 KB |
Output is correct |
2 |
Correct |
3 ms |
14940 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
19 ms |
17304 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
68 ms |
25460 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
75 ms |
27732 KB |
Output is correct |
2 |
Correct |
198 ms |
29052 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
144 ms |
27496 KB |
Output is correct |
2 |
Correct |
152 ms |
28480 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
170 ms |
28556 KB |
Output is correct |
2 |
Correct |
140 ms |
29504 KB |
Output is correct |