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#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <cmath>
using namespace std;
struct {
unsigned long long x, y;
} p[1000], m[1000000];
///p: A(x, y)
///m: dif de y/ dif de x => m[].x = dif de y
/// m[].y = dif de x
ifstream fin("trapez.in");
ofstream fout("trapez.out");
int cmmdc(int a, int b)
{
if( b != 0 )
return cmmdc(b, a%b);
else
return a;
}
int part_Hoare ( int s, int d )
{
int i, j;
i = s-1;
j= d+1;
int randpoz, r1, r2, r3;
int nr = d-s+1;
r1 = rand() % nr + s;
r2 = rand() % nr + s;
r3 = rand() % nr + s;
int minr, maxr;
minr = min ( min(r1, r2), min(r2, r3) );
maxr = max ( max(r1, r2), max(r2, r3) );
randpoz = r1+r2+r3 - minr-maxr;
int pivot_x = m[randpoz].x;
int pivot_y = m[randpoz].y;
while (true){
do
{
++i;
}while( m[i].x * pivot_y < m[i].y * pivot_x );
do
{
--j;
}while( m[j].x * pivot_y > m[j].y * pivot_x);
if( i>=j )
return j;
//swap
int aux_x, aux_y;
aux_x = m[i].x;
aux_y = m[i].y;
m[i].x = m[j].x;
m[i].y = m[j].y;
m[j].x = aux_x;
m[j].y = aux_y;
}
}
void qsort (int i, int j)
{
if(i<j){
int k = part_Hoare( i, j );
qsort(i, k);
qsort(k+1, j);
}
}
int main()
{
int n, i;
fin >> n;
for(i=0; i<n; i++)
fin >> p[i].x >> p[i].y;
int j, k=-1, m_0 = 0;;
for(i=0; i<n-1; i++)
for(j=i+1; j<n; j++)
{
if( p[i].x == p[j].x )
m_0++;
else
{
m[++k].x = p[i].y - p[j].y;
m[k].y = p[i].x - p[j].x;
int d = cmmdc( abs(m[k].x), abs(m[k].y) );
m[k].x /= d;
m[k].y /=d;
}
}
if( m_0 != 0 )
m_0++;
if( m_0 == 2 )
m_0 = 1;
else
if( m_0 > 2 )
m_0 *= m_0-1; ///combinari de m_0 luate cate 2
qsort(0, k);
int nr_total, nr_part;
if(m_0 != 0)
nr_total = m_0;
else
nr_total = 1;
i=1;
while ( i <= k )
{
nr_part = 0;
while( m[i].x * m[i-1].y == m[i].y * m[i-1].x )
{
nr_part++;
i++;
}
if(nr_part != 0) //pt ca numara x-1 nr egale in loc de x
nr_part++;
///daca nr_part e 2 atunci combinari de () o sa dea 1 si e elem neutru la inmultire
if(nr_part > 2)
{
nr_part = nr_part*(nr_part-1);
nr_total *= nr_part;
}
i++;
}
fout<<nr_total;
return 0;
}