#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;
using mint = modint998244353;

int main() {
  ll N; cin >> N;
  vector<ll> a(N), b(N), t(N);
  map<ll, ll> mp;
  for (int i = 0; i < N; i++) {
    cin >> a[i] >> b[i] >> t[i];
    if (a[i] == 0) {
      mp[b[i] - t[i]]++;
    }
  }
  ll ans = 0;
  for (int i = 0; i < N; i++) {
    if (a[i] == 1) {
      ans += mp[b[i] - t[i]];
    }
  }
  cout << ans << endl;
  return 0;
}