#include <bits/stdc++.h>
int N;
struct n_t{
    int x,y;
} f[500009];
bool cmp(n_t a,n_t b) {
    return a.x<b.x;
}
signed main(void) {
    scanf("%d",&N);
    for(int i=1;i<=N;i++) {
        scanf("%d %d",&f[i].x,&f[i].y);
    }
    long long ans=1ll*N*(N-1)*(N-2)/6;
    std::sort(f+1,f+N+1,cmp);
    for(int i=1;i<=N;i++) {
        int c1=0,c2=0;
        for(int j=1;j<i;j++) {
            if(f[i].x-f[j].x>abs(f[i].y-f[j].y)) c1++;
        }
        for(int j=i+1;j<=N;j++) {
            if(f[j].x-f[i].x>abs(f[i].y-f[j].y)) c2++;
        }
        ans-=1ll*c1*c2;
    }
    for(int i=1;i<=N;i++) std::swap(f[i].x,f[i].y);
    std::sort(f+1,f+N+1,cmp);
    for(int i=1;i<=N;i++) {
        int c1=0,c2=0;
        for(int j=1;j<i;j++) {
            if(f[i].x-f[j].x>abs(f[i].y-f[j].y)) c1++;
        }
        for(int j=i+1;j<=N;j++) {
            if(f[j].x-f[i].x>abs(f[i].y-f[j].y)) c2++;
        }
        ans-=1ll*c1*c2;
    }
    printf("%lld",ans);
}