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#include <cstdlib>
#include <algorithm>
#include <cstring>
#include <cctype>
#define INF 2000000000
using namespace std;
typedef long long ll;
int (){
int f=1,x=0;char c=getchar();
while(c<'0'||c>'9'){if(c=='-')f=-f;c=getchar();}
while(c>='0'&&c<='9')x=x*10+c-'0',c=getchar();
return f*x;
}
int n,x[205],y[205],tot=0;
double lis[40005],eps=1e-8;
double slope(int a,int b){
if(x[a]==x[b])return 1e9;
return (double)(y[b]-y[a])/(x[b]-x[a]);
}
int cmp(double a,double b){
return (a-b)>-eps&&(a-b)<eps;
}
void init(){
n=read();
for(int i=1;i<=n;i++)x[i]=read(),y[i]=read();
}
void solve(){
for(int i=1;i<=n;i++)
for(int j=1;j<i;j++)
lis[++tot]=slope(i,j);
sort(lis+1,lis+tot+1);
int ans=0;
for(int i=2;i<=tot;i++){
while(cmp(lis[i],lis[i-1])&&i<=tot)
i++;
ans++;
}
if(!cmp(lis[tot],lis[tot-1]))ans++;
printf("%dn",ans);
}
int main(){
init();
solve();
return 0;
}
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