#include <bits/stdc++.h>
#include <atcoder/dsu>
using namespace std;
using namespace atcoder;
using ll = long long;

ll isqrt(ll n) {
    ll ok = 0ll;
    ll ng = 2000000000ll;
    while(abs(ok - ng) > 1){
        ll mid = (ok + ng) / 2;
        if(mid * mid <= n){
            ok = mid;
        }
        else{
            ng = mid;
        }
    }
    return ok;
}

ll pow_ll(ll a, int b){
    ll ret = 1;
    for(int i = 0; i < b; ++i){
        ret *= a;
    }
    return ret;
}


int main(){
    int n;  cin >> n;
    vector<tuple<ll, ll, int> > planets(n);
    for(auto&[x, y, z] : planets){
        cin >> x >> y >> z;
    }

    vector<tuple<ll, int, int> > edges = {};
    for(int i = 0; i < n - 1; ++i){
        auto&[x1, y1, t1] = planets[i];
        for(int j = i + 1; j < n; ++j){
            auto&[x2, y2, t2] = planets[j];
            ll d = pow_ll(x1 - x2, 2) + pow_ll(y1 - y2, 2);
            if(t1 != t2){
                ll r1 = x1 * x1 + y1 * y1;
                ll r2 = x2 * x2 + y2 * y2;
                d = r1 + r2 - isqrt(4 * r1 * r2);
            }
            edges.push_back({d, i, j});
        }
    }
    sort(edges.begin(), edges.end());

    dsu uni(n);
    ll ans = 0;
    for(auto&[d, x, y] : edges){
        ans = d;
        uni.merge(x, y);
        if(!uni.same(0, n - 1)){
            continue;
        }
        break;
    }
    cout << ans << endl;

    return 0;
}