include[HTML_REMOVED]

using namespace std;

int main()
{
set[HTML_REMOVED]>s;
int x1,x2,y1,y2;
for(x1=0; x1<20; x1)
{
for(y1=0; y1<21; y1)
{
for(x2=0; x2<20; x2)
{
for(y2=0; y2<21; y2)
{
if(x1!=x2&&y1!=y2)
{
double k=(y2-y1)1.0/(x2-x1);//转换成double类型
double b=(y2(x2-x1)-(y2-y1)x2)1.0/(x2-x1);//避免因为k的精度而影响到b的精度
s.insert({k,b});
}

            }
        }
    }
}
cout<<s.size()+20+21<<endl;

}