#include <bits/stdc++.h>
#define maxN 100002
#define ll long long
#define pii pair < int, int >
using namespace std;

//FILE *fin = freopen("spt.in", "r", stdin);
//FILE *fout = freopen("spt.out", "w", stdout);

/* ---------------- */
int n, m;
/* ---------------- */
struct Coord
{
    int x, y, p;
} v[maxN], V[maxN];
int pos1[maxN], pos2[maxN], samex[maxN], samey[maxN], Q[maxN];
/* ---------------- */
map < pii, int > H;
/* ---------------- */
ll ans;

int cmpx(const Coord a, const Coord b)
{
    if (a.x == b.x)
        return a.y < b.y;
    return a.x < b.x;
}
int cmpy(const Coord a, const Coord b)
{
    if (a.y == b.y)
        return a.x < b.x;
    return a.y < b.y;
}

void read()
{
    scanf("%d", &n);
    for (int i = 1; i <= n; ++ i)
    {
        scanf("%d %d", &v[i].x, &v[i].y);
        ++ H[pii{v[i].x, v[i].y}];
        v[i].p = i;
        V[i] = v[i];
    }
}

void get_spt()
{
    int p = 1, q = 1;
    for (int i = 1; i <= n; ++ i)
    {
        if (V[i].y != V[q].y)
            q = i;
        Q[V[i].p] = q;
    }
    for (int i = 1; i <= n; ++ i)
    {
        if (v[i].x != v[p].x)
            p = i;
        q = Q[v[i].p];

        if (samex[p] < samey[q])
        {
            for (int j = p; v[j].x == v[i].x && j <= n; ++ j)
                if (j != i)
                {
                    //if ( H[pii{v[i].x + v[i].y - v[j].y, v[i].y}])
                    //    printf("%d %d %d %d %d %d\n", v[i].x, v[i].y, v[j].x, v[j].y, v[i].x + v[i].y - v[j].y, v[i].y);
                    ans += H[pii{v[i].x + v[i].y - v[j].y, v[i].y}];
                    if ( H[pii{v[i].x - v[i].y + v[j].y, v[i].y}])
                        printf("%d %d %d %d %d %d\n", v[i].x, v[i].y, v[j].x, v[j].y, v[i].x - v[i].y + v[j].y, v[i].y);
                    ans += H[pii{v[i].x - v[i].y + v[j].y, v[i].y}];

                    //ans += H[pii{v[i].x + v[i].y - v[j].y, v[j].y}];
                    //ans += H[pii{v[i].x - v[i].y + v[j].y, v[j].y}];
                }
        }
        else
            for (int j = q; V[j].y == V[pos2[v[i].p]].y && j <= n; ++ j)
                if (j != pos2[v[i].p])
                {
                    //if (H[pii{V[pos2[v[i].p]].x, V[pos2[v[i].p]].y + V[pos2[v[i].p]].x - V[j].x}])
                    //    printf("%d %d %d %d %d %d\n", V[pos2[v[i].p]].x, V[pos2[v[i].p]].y, V[j].x, V[j].y, V[pos2[v[i].p]].x, V[pos2[v[i].p]].y + V[pos2[v[i].p]].x - V[j].x);
                    ans += H[pii{V[pos2[v[i].p]].x, V[pos2[v[i].p]].y + V[pos2[v[i].p]].x - V[j].x}];
                    //if (H[pii{V[pos2[v[i].p]].x, V[pos2[v[i].p]].y - V[pos2[v[i].p]].x + V[j].x}])
                    //    printf("%d %d %d %d %d %d\n", V[pos2[v[i].p]].x, V[pos2[v[i].p]].y, V[j].x, V[j].y, V[pos2[v[i].p]].x, V[pos2[v[i].p]].y - V[pos2[v[i].p]].x + V[j].x);
                    ans += H[pii{V[pos2[v[i].p]].x, V[pos2[v[i].p]].y - V[pos2[v[i].p]].x + V[j].x}];

                    //ans += H[pii{V[j].x, V[pos2[v[i].p]].y + V[pos2[v[i].p]].x - V[j].x}];
                    //ans += H[pii{V[j].x, V[pos2[v[i].p]].y - V[pos2[v[i].p]].x + V[j].x}];
                }

    }
}

void solve()
{
    sort(v + 1, v + n + 1, cmpx);
    sort(V + 1, V + n + 1, cmpy);
    int p = 1, q = 1;
    for (int i = 1; i <= n; ++ i)
    {
        if (v[i].x == v[p].x)
            ++ samex[p];
        else
        {
            p = i;
            ++ samex[p];
        }
        if (V[i].y != V[q].y)
            q = i;
        ++ samey[q];

        pos1[v[i].p] = i;
        pos2[V[i].p] = i;
    }
    get_spt();
}

void write()
{
    printf("%lld\n", ans);
}

int main()
{
    read();
    solve();
    write();
    return 0;
}