#include <math.h>
#include <bits/stdc++.h>
#include <atcoder/all>
#define rep(i, l, n) for (int i = (l); i < (n); i++)
#define squ(n) (n) * (n)
using namespace std;
using namespace atcoder;
using ll = long long;
template <class T>	using V = vector<T>;
template <class T>	using PQ = priority_queue<T, V<T>, greater<T> >;

ll isqrt(ll n) {
	double rn = sqrt(double(n));
	ll ok = max(0ll, (ll)(rn - 5.0));
	ll ng = (ll)(rn + 5.0);
	while (ng - ok > 1ll) {
		ll mid = (ok + ng) >> 1ll;
		if (mid * mid <= n) {
			ok = mid;
		}
		else {
			ng = mid;
		}
	}
	return ok;
}


int main(void) {
	int n;	cin >> n;
	V<V<ll> > p(n, V<ll>(3));
	rep(i, 0, n) {
		ll x, y, t;	cin >> x >> y >> t;
		p[i] = { x,y,t };
	}

	PQ<V<ll> > que = {};
	rep(i, 0, n-1) {
		ll r1 = squ(p[i][0]) + squ(p[i][1]);
		rep(j, i + 1, n) {
			ll r2 = squ(p[j][0]) + squ(p[j][1]);
			ll d = squ(p[i][0] - p[j][0]) + squ(p[i][1] - p[j][1]);
			if (p[i][2] != p[j][2]) {
				d = r1 + r2 - isqrt(4ll * r1 * r2);
			}
			que.push({ d,(ll)i,(ll)j });
		}
	}

	ll ans = 0ll;
	dsu uni(n);
	while (uni.same(0, n - 1) == false) {
		V<ll> v = que.top();	que.pop();
		ans = v[0];
		uni.merge(v[1], v[2]);
	}
	cout << ans << endl;

	return 0;
}