#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pullull;
typedef pair<ll, int> plli;
typedef pair<int, pii> pipii;
typedef vector<vector<int> > mati;
typedef vector<vector<double> > matd;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<vector<vector<ll>>> vvvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vector<vector<bool>>> vvvb;
typedef vector<pll> vpll;

#define FOR(i,x,y) for(ll i=(ll)x; i<(ll)y; ++i)
#define REP(i,y) FOR(i, 0, y)
#define RFOR(i,x,y) for(ll i=(ll)x; i>=(ll)y; --i)
#define RREP(i,x) RFOR(i, x, 0)
#define ALL(a) a.begin(), a.end()
#define pb push_back

inline void IN(void){
  return;
}

template <typename First, typename... Rest>
void IN(First& first, Rest&... rest){
  cin >> first;
  IN(rest...);
  return;
}

inline void OUT(void){
  cout << "\n";
  return;
}

template <typename First, typename... Rest>
void OUT(First first, Rest... rest){
  cout << first << " ";
  OUT(rest...);
  return;
}

template <typename T>
void vec_print(vector<T> VEC){
  REP(i, VEC.size()){
    cout << VEC[i] << " ";
  }
  cout << "\n";
};

template <typename T>
void mat_print(vector<vector<T> > MAT){
  REP(i, MAT.size()){
    REP(j, MAT[i].size()){
      cout << MAT[i][j] << " ";
    }
    cout << "\n";
  }
};

template <typename CLASS1, typename CLASS2>
class HOGE{
  public:
    CLASS1 key;
    CLASS2 value;
    HOGE(void){
      return;
    };
    HOGE(CLASS1 key, CLASS2 value){
      this->key = key;
      this->value = value;
    };
    ~HOGE(void){
      return;
    };

    void print(void){
      cout << "key : " << key << ", value : " << value << "\n";
      return;
    };
    
    bool operator==(const HOGE &obj){
      return (this->value == obj.value);
    };
    bool operator<(const HOGE &obj){
      return (this->value < obj.value);
    };
    bool operator>(const HOGE &obj){
      return (this->value > obj.value);
    };
};

template <typename CLASS1, typename CLASS2>
bool operator==(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value == hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator<(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value < hoge2.value;
};

template <typename CLASS1, typename CLASS2>
bool operator>(const HOGE<CLASS1, CLASS2> &hoge1, const HOGE<CLASS1, CLASS2> &hoge2){
  return hoge1.value > hoge2.value;
};

constexpr int INF = (1<<30);
constexpr ll INFLL = 1LL<<62;
constexpr long double EPS = 1e-12;
constexpr ll MOD = (ll)((1E+9)+7);

constexpr ll L_MAX = (ll)((1E+5)+7);

ll search_x(const ll, ll&, ll&);
ll search_y(const ll, ll&, ll&);

vvll xPath(L_MAX), yPath(L_MAX);
vb x_flag(L_MAX, true), y_flag(L_MAX, true);
map<ll, bool> mp;

ll H(ll x, ll y){
  return x*((1E+5)+10) + y;
}

ll search_x(const ll y, ll& x_kind, ll& y_kind){
  ll ans = 0;
  if(!y_flag[y]) return ans;
  y_flag[y] = false;
  y_kind++;

  REP(i,yPath[y].size()){
    if(mp[H(yPath[y][i], y)]){
      ans++;
      mp[H(yPath[y][i], y)] = false;

      //fprintf(stderr, "%lld %lld\n", yPath[y][i], y);
      ans += search_y(yPath[y][i], x_kind, y_kind);
    }
  }
  return ans;
}

ll search_y(const ll x, ll& x_kind, ll& y_kind){
  ll ans = 0;
  if(!x_flag[x]) return ans;
  x_flag[x] = false;
  x_kind++;

  REP(i,xPath[x].size()){
    if(mp[H(x, xPath[x][i])]){
      ans++;
      mp[H(x, xPath[x][i])] = false;

      //fprintf(stderr, "%lld %lld\n", x, xPath[x][i]);
      ans += search_x(xPath[x][i], x_kind, y_kind);
    }
  }
  return ans;
}

int main(){
  cin.tie(0); // cut the cin and cout (default, std::flush is performed after std::cin)
  ios::sync_with_stdio(false); // cut the iostream and stdio (DON'T endl; BUT "\n";)

  ll N;
  IN(N);

  vll x(N), y(N);
  REP(i,N){
    IN(x[i], y[i]);
    xPath[x[i]].pb(y[i]);
    yPath[y[i]].pb(x[i]);
    mp[H(x[i], y[i])] = true;
  }

  ll ans=0;
  REP(i,N){
    ll count = 0;
    ll x_kind=0, y_kind=0;
    count += search_y(x[i], x_kind, y_kind);

    ans += x_kind*y_kind - count;

    //fprintf(stderr, "%lld %lld %lld\n", x_kind, y_kind, count);

  }

  OUT(ans);

  return 0;
}


Measured memory_bytes: 26752