#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <algorithm>
#define MOD 666013
#define MAXN 1000

#define BUF_SIZE 16384
char buf[BUF_SIZE];
int pbuf=BUF_SIZE;
FILE*fi,*fo;
inline char nextch(){
    if(pbuf==BUF_SIZE){
        fread(buf, BUF_SIZE, 1, fi);
        pbuf=0;
    }
    return buf[pbuf++];
}
inline long long nextnum(){
    long long a=0;
    char c=nextch();
    while((c<'0' || c>'9') && c!='-')
        c=nextch();
    int semn=1;
    if(c=='-'){
        semn=-1;
        c=nextch();
    }
    while(('0'<=c && c<='9') || c=='.'){
        if(c!='.')
            a=a*10+c-'0';
        c=nextch();
    }
    return a*semn;
}
class Hash{
    public:
    long long k=0, next[MAXN+1], *lista;
    long long val[MAXN+1];
    long long d[MAXN+1];
    Hash() {
        lista = new long long[MOD];
        memset(lista, 0x00, MOD*sizeof(int));
    }
    inline void insert(long long x, long long y, long long frecventa){
        k++;
        val[k]=y;
        d[k]=frecventa;
        next[k]=lista[(1LL*x+1LL*MOD*MOD)%MOD];
        lista[(1LL*x+1LL*MOD*MOD)%MOD]=k;
    }
    inline void erase(long long element){
        long long p=lista[(1LL*element+1LL*MOD*MOD)%MOD];
        if(p==0)
            return ;
        if(val[p]==element){
            lista[(1LL*element+1LL*MOD*MOD)%MOD]=next[lista[(1LL*element+1LL*MOD*MOD)%MOD]];
            return ;
        }
        while(next[p]!=0 && val[next[p]]!=element)
            p=next[p];
        if(next[p]!=0){
            next[p]=next[next[p]];
        }
    }
    inline long long find(long long x, long long y){
        long long p=lista[(1LL*x+1LL*MOD*MOD)%MOD];
        while(p!=0 && val[p]!=y)
            p=next[p];
        if(p!=0)
            return p;
        return 0;
    }
} H;

struct Point{
    int x, y;
}v[MAXN+1];
inline int M(Point A, Point B){
    if(A.y>B.y)
        return 1;
    if(A.y==B.y && A.x>B.x)
        return 1;
    return 0;
}
inline int m(Point A, Point B){
    if(A.y<B.y)
        return 1;
    if(A.y==B.y && A.x<B.x)
        return 1;
    return 0;
}

void q(int begin, int end){
    int b=begin, e=end;
    Point p=v[(b+e)/2];
    while(b<=e){
        while(m(v[b], p)) b++;
        while(M(v[e], p)) e--;
        if(b<=e){
            Point aux=v[b];
            v[b]=v[e];
            v[e]=aux;
            b++;
            e--;
        }
    }
    if(b<end) q(b, end);
    if(begin<e) q(begin, e);
}

int main(){
    fi=fopen("patrate3.in","r");
    fo=fopen("patrate3.out","w");
    int n=nextnum();
    for(int i=1;i<=n;i++){
        v[i].x=nextnum();
        v[i].y=nextnum();
    }
    q(1, n);
    int squares=0;
    for(int i=1;i<=n;i++)
        H.insert(v[i].x, v[i].y, 1);
    for(int i=1;i<=n;i++)
        for(int j=i+1;j<=n;j++){
            if(v[i].x>v[j].x){
                //printf("%lld %lld", H.find(v[i].x-(v[i].y-v[j].y), v[i].y-(v[j].x-v[i].x)), H.find(v[j].x-(v[i].y-v[j].y), v[j].y-(v[j].x-v[i].x)));
                if(H.find(v[i].x-(v[i].y-v[j].y), v[i].y+(v[i].x-v[j].x)) && H.find(v[j].x-(v[i].y-v[j].y), v[j].y+(v[i].x-v[j].x)))
                    squares++;
                if(H.find(v[i].x+(v[i].y-v[j].y), v[i].y-(v[i].x-v[j].x)) && H.find(v[j].x+(v[i].y-v[j].y), v[j].y-(v[i].x-v[j].x)))
                    squares++;
            }
            else{
                if(H.find(v[i].x+(v[i].y-v[j].y), v[i].y+(v[j].x-v[i].x)) && H.find(v[j].x+(v[i].y-v[j].y), v[j].y+(v[j].x-v[i].x)))
                    squares++;
                if(H.find(v[i].x-(v[i].y-v[j].y), v[i].y-(v[j].x-v[i].x)) && H.find(v[j].x-(v[i].y-v[j].y), v[j].y-(v[j].x-v[i].x)))
                    squares++;
            }
        }
    fprintf(fo,"%d", squares/4);
    fclose(fi);
    fclose(fo);
    return 0;
}