#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
typedef long long ll;
int n;
struct point
{
int x,y,ang;
} v[100005],angle[100005];
bool comp(point a, point b)
{
return a.y*b.x<a.x*b.y;
}
map<pii,int> nrm;
bool cmp(int a, int b)
{
if(v[a].ang!=v[b].ang)
return v[a].ang<v[b].ang;
return v[a].y<v[b].y;
}
bool use[100005],spec[100005];
int aib[100005],times[100005];
int lsb(int x)
{
return x&(-x);
}
void update(int poz,int val)
{
for(int i=poz;i<=n;i+=lsb(i))
aib[i]+=val;
}
int suma(int poz)
{
int rez=0;
for(int i=poz;i>=1;i-=lsb(i))
rez+=aib[i];
return rez;
}
int cur=0;
bool iseq(point a, point b)
{
return a.x==b.x&&a.y==b.y;
}
ll aria(point A, point B)
{
ll rez=1LL*A.x*B.y-1LL*A.y*B.x;
rez=abs(rez);
return rez;
}
bool intersect(point A, point B, point C)
{
if(iseq(A,C)||iseq(B,C))
return 0;
if(A.ang>B.ang)
swap(A,B);
if(C.ang>=A.ang&&C.ang<=B.ang)
if(aria(A,C)+aria(B,C)>=aria(A,B))
return 1;
return 0;
}
bool checkgood(int i)
{
if(cur==0)
return 1;
point a=v[cur];
int lft=cur-1;
if(lft<1)
lft=n;
point b=v[lft];
if(intersect(a,b,v[i]))
return 0;
int rgt=cur+1;
if(rgt>n)
rgt=1;
b=v[rgt];
if(intersect(a,b,v[i]))
return 0;
return 1;
}
int main()
{
cin>>n;
for(int i=1;i<=n;i++)
{
int x,y;
cin>>x>>y;
v[i]={x,y,0};
int cmmdc=__gcd(x,y);
x/=cmmdc;
y/=cmmdc;
angle[i]={x,y,0};
}
sort(angle+1,angle+n+1,comp);
// cout<<'\n';
for(int i=1;i<=n;i++)
{
pii a={angle[i].x,angle[i].y};
nrm[a]=i;
}
for(int i=1;i<=n;i++)
{
int cmmdc=__gcd(v[i].x,v[i].y);
int xa=v[i].x/cmmdc,ya=v[i].y/cmmdc;
v[i].ang=nrm[{xa,ya}];
}
vector<int> ind;
for(int i=1;i<=n;i++)
ind.push_back(i);
sort(ind.begin(),ind.end(),cmp);
vector<int> sol;
int nr=0;
for(int i:ind)
{
nr++;
bool good=checkgood(i);
if(good)
{
cur=i;
sol.push_back(i);
}
}
sort(sol.begin(),sol.end());
cout<<sol.size()<<'\n';
for(int i:sol)
cout<<i<<' ';
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
212 KB |
Output isn't correct |
2 |
Correct |
1 ms |
340 KB |
Output is correct |
3 |
Correct |
3 ms |
596 KB |
Output is correct |
4 |
Correct |
4 ms |
724 KB |
Output is correct |
5 |
Incorrect |
12 ms |
1236 KB |
Output isn't correct |
6 |
Incorrect |
14 ms |
1208 KB |
Output isn't correct |
7 |
Incorrect |
25 ms |
2160 KB |
Output isn't correct |
8 |
Incorrect |
10 ms |
972 KB |
Output isn't correct |
9 |
Correct |
8 ms |
980 KB |
Output is correct |
10 |
Incorrect |
13 ms |
1236 KB |
Output isn't correct |
11 |
Incorrect |
14 ms |
1376 KB |
Output isn't correct |
12 |
Correct |
20 ms |
2132 KB |
Output is correct |
13 |
Incorrect |
40 ms |
3116 KB |
Output isn't correct |
14 |
Correct |
43 ms |
4116 KB |
Output is correct |
15 |
Correct |
52 ms |
4896 KB |
Output is correct |
16 |
Execution timed out |
107 ms |
9524 KB |
Time limit exceeded |
17 |
Execution timed out |
149 ms |
9532 KB |
Time limit exceeded |
18 |
Runtime error |
59 ms |
5068 KB |
Execution killed with signal 11 |
19 |
Runtime error |
63 ms |
5068 KB |
Execution killed with signal 11 |
20 |
Execution timed out |
125 ms |
8056 KB |
Time limit exceeded |