#include "parks.h"
#include <map>
#include <utility>
#include <queue>
#include <set>
using namespace std;
map < pair < int , int > , int > all,con;
map < pair < int , int > , pair < int , int > > road;
vector < int > u,v,a,b;
queue < pair < int , int > > BFS;
set < pair < int , int > > still;
int Father[200005];
int Find(int here)
{
if(Father[here]==here) return here;
Father[here]=Find(Father[here]);
return Father[here];
}
int construct_roads(vector < int > x, vector < int > y)
{
int N=x.size(),i,t,aa,bb,ok=1,xx,yy,big;
for(i=0;i<N;i++)
{
all[make_pair(x[i],y[i])]=i;
Father[i]=i;
big=max(big,x[i]);
}
if(big<=6)
{
for(i=0;i<N;i++)
{
if(all.find(make_pair(x[i],y[i]+2))!=all.end())
{
t=all[make_pair(x[i],y[i]+2)];
aa=Find(i);
bb=Find(t);
if(aa!=bb) Father[aa]=bb;
if(x[i]==2)
{
u.push_back(i);
v.push_back(t);
a.push_back(x[i]-1);
b.push_back(y[i]+1);
}
else if(x[i]==4)
{
if(y[i]%4==0)
{
u.push_back(i);
v.push_back(t);
a.push_back(x[i]-1);
b.push_back(y[i]+1);
}
else
{
u.push_back(i);
v.push_back(t);
a.push_back(x[i]+1);
b.push_back(y[i]+1);
}
}
else if(x[i]==6)
{
u.push_back(i);
v.push_back(t);
a.push_back(x[i]+1);
b.push_back(y[i]+1);
}
}
if(all.find(make_pair(x[i]+2,y[i]))!=all.end())
{
t=all[make_pair(x[i]+2,y[i])];
aa=Find(i);
bb=Find(t);
if(aa!=bb) Father[aa]=bb;
if(y[i]%4==0)
{
if(x[i]==2)
{
u.push_back(i);
v.push_back(t);
a.push_back(x[i]+1);
b.push_back(y[i]-1);
}
else
{
u.push_back(i);
v.push_back(t);
a.push_back(x[i]+1);
b.push_back(y[i]+1);
}
}
else
{
Not.insert(make_pair(i,t));
}
}
}
M=a.size();
for(i=0;i<M;i++) have.insert(make_pair(a[i],b[i]));
for(auto i:Not)
{
if(have.find(make_pair(x[i.first]+1,y[i.first]+1))==have.end())
{
have.insert(make_pair(x[i.first]+1,y[i.first]+1));
u.push_back(i.first);
v.push_back(i.second);
a.push_back(x[i.first]+1);
b.push_back(y[i.first]+1);
}
else if(have.find(make_pair(x[i.first]+1,y[i.first]-1))==have.end())
{
have.insert(make_pair(x[i.first]+1,y[i.first]-1));
u.push_back(i.first);
v.push_back(i.second);
a.push_back(x[i.first]+1);
b.push_back(y[i.first]-1);
}
}
t=Find(0);
for(i=0;i<N;i++)
{
//printf("%d %d\n",t,Find(i));
if(t!=Find(i)) ok=0;
}
if(ok==0) return ok;
if(ok) build(u,v,a,b);
return ok;
}
else
{
for(i=0;i<N;i++)
{
if(all.find(make_pair(x[i],y[i]+2))!=all.end())
{
t=all[make_pair(x[i],y[i]+2)];
road[make_pair(x[i],y[i]+1)]=make_pair(i,t);
con[make_pair(x[i]+1,y[i]+1)]++;
con[make_pair(x[i]-1,y[i]+1)]++;
aa=Find(i);
bb=Find(t);
if(aa!=bb) Father[aa]=bb;
}
if(all.find(make_pair(x[i]+2,y[i]))!=all.end())
{
t=all[make_pair(x[i]+2,y[i])];
road[make_pair(x[i]+1,y[i])]=make_pair(i,t);
con[make_pair(x[i]+1,y[i]+1)]++;
con[make_pair(x[i]+1,y[i]-1)]++;
aa=Find(i);
bb=Find(t);
if(aa!=bb) Father[aa]=bb;
}
}
t=Find(0);
for(i=0;i<N;i++) if(t!=Find(i)) ok=0;
if(ok==0) return ok;
for(auto i:con)
{
still.insert(i.first);
if(i.second==1) BFS.push(i.first);
}
while(!BFS.empty())
{
xx=BFS.front().first;
yy=BFS.front().second;
BFS.pop();
still.erase(make_pair(xx,yy));
if(con[make_pair(xx,yy)]<=0) continue;
if(road.find(make_pair(xx+1,yy))!=road.end()) aa=xx+1,bb=yy;
if(road.find(make_pair(xx-1,yy))!=road.end()) aa=xx-1,bb=yy;
if(road.find(make_pair(xx,yy+1))!=road.end()) aa=xx,bb=yy+1;
if(road.find(make_pair(xx,yy-1))!=road.end()) aa=xx,bb=yy-1;
u.push_back(road[make_pair(aa,bb)].first);
v.push_back(road[make_pair(aa,bb)].second);
a.push_back(xx);
b.push_back(yy);
road.erase(make_pair(aa,bb));
con[make_pair(xx,yy)]=0;
if(aa%2==0)
{
con[make_pair(aa-1,bb)]--;
con[make_pair(aa+1,bb)]--;
if(con[make_pair(aa-1,bb)]==1) BFS.push(make_pair(aa-1,bb));
if(con[make_pair(aa+1,bb)]==1) BFS.push(make_pair(aa+1,bb));
}
else
{
con[make_pair(aa,bb-1)]--;
con[make_pair(aa,bb+1)]--;
if(con[make_pair(aa,bb-1)]==1) BFS.push(make_pair(aa,bb-1));
if(con[make_pair(aa,bb+1)]==1) BFS.push(make_pair(aa,bb+1));
}
}
while(!still.empty())
{
BFS.push(*still.begin());
while(!BFS.empty())
{
ok=0;
xx=BFS.front().first;
yy=BFS.front().second;
BFS.pop();
still.erase(make_pair(xx,yy));
if(con[make_pair(xx,yy)]<=0) continue;
if(road.find(make_pair(xx+1,yy))!=road.end()) aa=xx+1,bb=yy,ok=1;
if(road.find(make_pair(xx-1,yy))!=road.end()) aa=xx-1,bb=yy,ok=1;
if(road.find(make_pair(xx,yy+1))!=road.end()) aa=xx,bb=yy+1,ok=1;
if(road.find(make_pair(xx,yy-1))!=road.end()) aa=xx,bb=yy-1,ok=1;
con[make_pair(xx,yy)]=0;
if(ok==0) continue;
u.push_back(road[make_pair(aa,bb)].first);
v.push_back(road[make_pair(aa,bb)].second);
a.push_back(xx);
b.push_back(yy);
road.erase(make_pair(aa,bb));
if(aa%2==0)
{
con[make_pair(aa-1,bb)]--;
con[make_pair(aa+1,bb)]--;
if(con[make_pair(aa-1,bb)]==1) BFS.push(make_pair(aa-1,bb));
if(con[make_pair(aa+1,bb)]==1) BFS.push(make_pair(aa+1,bb));
}
else
{
con[make_pair(aa,bb-1)]--;
con[make_pair(aa,bb+1)]--;
if(con[make_pair(aa,bb-1)]==1) BFS.push(make_pair(aa,bb-1));
if(con[make_pair(aa,bb+1)]==1) BFS.push(make_pair(aa,bb+1));
}
}
}
if(!road.empty()) return 0;
if(ok) build(u,v,a,b);
return ok;
}
}
Compilation message
parks.cpp: In function 'int construct_roads(std::vector<int>, std::vector<int>)':
parks.cpp:96:21: error: 'Not' was not declared in this scope
96 | Not.insert(make_pair(i,t));
| ^~~
parks.cpp:100:9: error: 'M' was not declared in this scope
100 | M=a.size();
| ^
parks.cpp:101:26: error: 'have' was not declared in this scope
101 | for(i=0;i<M;i++) have.insert(make_pair(a[i],b[i]));
| ^~~~
parks.cpp:102:20: error: 'Not' was not declared in this scope
102 | for(auto i:Not)
| ^~~
parks.cpp:104:16: error: 'have' was not declared in this scope
104 | if(have.find(make_pair(x[i.first]+1,y[i.first]+1))==have.end())
| ^~~~
