QOJ.ac
QOJ
| ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
|---|---|---|---|---|---|---|---|---|---|
| #592472 | #7081. Cut the Plane | Afterlife | WA | 0ms | 3616kb | C++20 | 9.0kb | 2024-09-26 22:48:44 | 2024-09-26 22:48:45 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=1e2+1e1+7,L=12;
struct P{
int x,y;
P(int _x=0,int _y=0){x=_x,y=_y;}
};
P operator *(const P &a,const int &b)
{
return {a.x*b,a.y*b};
}
P operator -(const P &a,const P &b)
{
return {a.x-b.x,a.y-b.y};
}
P operator +(const P &a,const P &b)
{
return {a.x+b.x,a.y+b.y};
}
int T;
int sgn(int x)
{
return x<-0?-1:(x>0);
}
int det(P a,P b)
{
return a.x*b.y-a.y*b.x;
}
int dot(P a,P b)
{
return a.x*b.x+a.y*b.y;
}
int in_seg(P a,P b,P c)
{
return sgn(det(b-a,c-a))==0&&sgn(dot(a-c,b-c))<=0;
}
int segment_intersection(P a,P b,P c,P d)
{
if(sgn(det(b-a,c-a))*sgn(det(b-a,d-a))==-1&&sgn(det(d-c,a-c))*sgn(det(d-c,b-c))==-1)
return 1;
if(in_seg(a,b,d)||in_seg(a,b,c)||in_seg(c,d,a)||in_seg(c,d,b))
return 1;
return 0;
}
signed main()
{
ios::sync_with_stdio(false);
cin.tie(0);
cin>>T;
while(T--)
{
int n;
cin>>n;
// n=100;
vector<P>p(n);
for(auto &[x,y]:p)
{
// x=rand()%10000,y=rand()%10000;
// x*=2,y*=2;
cin>>x>>y;
}
if(n==1)
{
cout<<(int)1e8<<" "<<(int)1e8<<" "<<(int)1e8+1<<" "<<(int)1e8<<"\n";
continue;
}
sort(p.begin(),p.end(),[&](const P &a,const P &b){
if(a.y!=b.y)
return a.y<b.y;
return a.x>b.x;
});
int h=n/2;
P m=(p[h-1]+p[h]);
m.x/=2,m.y/=2;
vector<pair<P,P> >ans;
P A=m+P(1e8,0);
P B=m+P(-1e8,0);
P mab,mcd;
while(1)
{
mab=A,mcd=B;
mab.x+=rand()%L-L/2;
mab.y+=rand()%L-L/2;
mcd.x+=rand()%L-L/2;
mcd.y+=rand()%L-L/2;
int ok=1;
for(int i=0;i<n;i++)
{
if(in_seg(mab,mcd,p[i]))
{
ok=0;
break;
}
}
for(int i=0;i<h;i++)
{
if(!ok)
break;
for(int j=h;j<n;j++)
if(!segment_intersection(p[i],p[j],mab,mcd))
{
ok=0;
break;
}
}
if(ok)
break;
}
ans.push_back({mab,mcd});
sort(p.begin(),p.begin()+h,[&](const P &a,const P &b){
if(a.x!=b.x)
return a.x<b.x;
return a.y<b.y;
});
sort(p.begin()+h,p.begin()+n,[&](const P &a,const P &b){
if(a.x!=b.x)
return a.x<b.x;
return a.y<b.y;
});
// int u=0,v=h;
using pii=pair<int,int>;
queue<pii> q1,q2;
for(int i=0;i<h;i++)
for(int j=i+1;j<h;j++)
q1.push({i,j});
for(int i=h;i<n;i++)
for(int j=i+1;j<n;j++)
q2.push({i,j});
while(!q1.empty()&&!q2.empty())
{
while(q1.size())
{
auto [a,b]=q1.front();
int ok=0;
for(auto [u,v]:ans)
if(segment_intersection(p[a],p[b],u,v))
{
ok=1;
break;
}
if(ok)
q1.pop();
else
break;
}
while(q2.size())
{
auto [a,b]=q2.front();
int ok=0;
for(auto [u,v]:ans)
if(segment_intersection(p[a],p[b],u,v))
{
ok=1;
break;
}
if(ok)
q2.pop();
else
break;
}
if(!q1.size()||!q2.size())
break;
auto [ia,ib]=q1.front();
auto [ic,id]=q2.front();
q1.pop(),q2.pop();
P a=p[ia],b=p[ib],c=p[ic],d=p[id];
P mab=a+b;
mab.x/=2,mab.y/=2;
P mcd=c+d;
mcd.x/=2,mcd.y/=2;
P dir=a+b-c-d;
mab=mab+dir*50000;
mcd=mcd-dir*50000;
P A=mab,B=mcd;
int lim=10,ok=1;
while(lim--)
{
mab=A;
mcd=B;
mab.x+=rand()%L-L/2;
mcd.x+=rand()%L-L/2;
mab.y+=rand()%L-L/2;
mcd.y+=rand()%L-L/2;
ok=1;
for(int i=0;i<n;i++)
{
if(!ok)
break;
if(in_seg(mab,mcd,p[i]))
ok=0;
}
if(!segment_intersection(mab,mcd,a,b)||!segment_intersection(mab,mcd,c,d))
ok=0;
if(ok)
break;
}
if(!ok)
{
q1.push({ia,ib});
q2.push({ic,id});
}
ans.push_back({mab,mcd});
}
while(q1.size())
{
while(q1.size())
{
auto [a,b]=q1.front();
int ok=0;
for(auto [u,v]:ans)
if(segment_intersection(p[a],p[b],u,v))
{
ok=1;
break;
}
if(ok)
q1.pop();
else
break;
}
if(!q1.size())
break;
P a=p[q1.front().first],b=p[q1.front().second];
q1.pop();
P m=(a+b);
m.x/=2,m.y/=2;
P A=P(m.x,m.y+1e8),B=P(m.x,m.y-1e8);
P mab,mcd;
while(1)
{
mab=A;
mcd=B;
mab.x+=rand()%L-L/2;
mcd.x+=rand()%L-L/2;
mab.y+=rand()%L-L/2;
mcd.y+=rand()%L-L/2;
int ok=1;
for(int i=0;i<n;i++)
{
if(!ok)
break;
if(in_seg(mab,mcd,p[i]))
ok=0;
}
if(!segment_intersection(mab,mcd,a,b))
ok=0;
if(ok)
break;
}
ans.push_back({mab,mcd});
}
while(q2.size())
{
while(q2.size())
{
auto [a,b]=q2.front();
int ok=0;
for(auto [u,v]:ans)
if(segment_intersection(p[a],p[b],u,v))
{
ok=1;
break;
}
if(ok)
q2.pop();
else
break;
}
if(!q2.size())
break;
P a=p[q2.front().first],b=p[q2.front().second];
q2.pop();
P m=(a+b);
m.x/=2,m.y/=2;
P A=P(m.x,m.y+1e8),B=P(m.x,m.y-1e8);
P mab,mcd;
while(1)
{
mab=A;
mcd=B;
mab.x+=rand()%L-L/2;
mcd.x+=rand()%L-L/2;
mab.y+=rand()%L-L/2;
mcd.y+=rand()%L-L/2;
int ok=1;
for(int i=0;i<n;i++)
{
if(!ok)
break;
if(in_seg(mab,mcd,p[i]))
ok=0;
}
if(!segment_intersection(mab,mcd,a,b))
ok=0;
if(ok)
break;
}
ans.push_back({mab,mcd});
}
for(auto &[a,b]:ans)
{
cout<<a.x<<" "<<a.y<<" "<<b.x<<" "<<b.y<<"\n";
}
int z=1e8;
int tot=(n+1)/2;
while(ans.size()<tot)
{
cout<<(int)z<<" "<<(int)z<<" "<<(int)z+1<<" "<<(int)z<<"\n";
z++;
tot--;
}
// int ok=1;
// // ok&=ans.size()==(n+1)/2;
// for(int i=0;i<n;i++)
// {
// for(auto [u,v]:ans)
// {
// if(in_seg(u,v,p[i]))
// ok=0;
// }
// for(int j=i+1;j<n;j++)
// {
// int flag=0;
// for(auto [u,v]:ans)
// if(segment_intersection(p[i],p[j],u,v))
// flag=1;
// ok&=flag;
// }
// }
// cout<<ok<<endl;
}
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3564kb
input:
2 3 0 0 2 1 4 0 4 0 1 1 0 2 1 1 2
output:
99999998 4 -99999995 -4 1 99999995 3 -100000003 99999999 6 -99999996 -4 100006 -99996 -100005 99999
result:
ok 2 cases
Test #2:
score: -100
Wrong Answer
time: 0ms
memory: 3616kb
input:
4 2 0 0 3 0 3 0 0 3 0 3 3 4 0 0 3 0 3 3 0 3 4 0 0 3 0 1 1 0 3
output:
99999997 4 -99999996 -4 99999999 4 -99999995 -4 1 99999995 1 -100000005 99999996 3 -99999999 1 2 -299998 1 300006 100000000 3 -99999998 -2 99995 -200005 -100001 199996 100000 -200000 -100000 200006
result:
wrong answer In case 4, there exist two points lie in the same piece.