import java.io.*;
import java.util.*;
import java.util.stream.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int n = sc.nextInt();
        Point[] points = new Point[n];
        for (int i = 0; i < n; i++) {
            points[i] = new Point(sc.nextInt(), sc.nextInt(), sc.nextInt());
        }
        PriorityQueue<Distance> queue = new PriorityQueue<>();
        for (int i = 0; i < n; i++) {
            for (int j = i + 1; j < n; j++) {
                queue.add(new Distance(i, j, points[i].getDistance(points[j])));
            }
        }
        long current = 0;
        UnionFindTree uft = new UnionFindTree(n);
        while (!uft.same(0, n - 1)) {
            Distance x = queue.poll();
            uft.unite(x);
            current = x.value;
        }
        System.out.println(current);
    }
    
    static class UnionFindTree {
        int[] parents;
        
        public UnionFindTree(int size) {
            parents = new int[size];
            for (int i = 0; i < size; i++) {
                parents[i] = i;
            }
        }
        
        public int find(int x) {
            if (x == parents[x]) {
                return x;
            } else {
                return parents[x] = find(parents[x]);
            }
        }
        
        public boolean same(int x, int y) {
            return find(x) == find(y);
        }
        
        public void unite(int x, int y) {
            if (!same(x, y)) {
                parents[find(x)] = find(y);
            }
        }
        
        public void unite(Distance x) {
            unite(x.left, x.right);
        }
    }
    
    static class Distance implements Comparable<Distance> {
        int left;
        int right;
        long value;
        
        public Distance(int left, int right, long value) {
            this.left = left;
            this.right = right;
            this.value = value;
        }
        
        public int compareTo(Distance another) {
            if (value == another.value) {
                return 0;
            } else if (value < another.value) {
                return -1;
            } else {
                return 1;
            }
        }
    }
    
    static class Point {
        long x;
        long y;
        int t;
        long r2;
        
        public Point(long x, long y, int t) {
            this.x = x;
            this.y = y;
            this.t = t;
            r2 = x * x + y * y;
        }
        
        public long getDistance(Point p) {
            if (t == p.t) {
                return (x - p.x) * (x - p.x) + (y - p.y) * (y - p.y);
            } else {
                long ans = r2 + p.r2;
                long left = 0;
                long right = Integer.MAX_VALUE;
                while (right - left > 1) {
                    long m = (left + right) / 2;
                    if (m * m <= 4 * r2 * p.r2) {
                        left = m;
                    } else {
                        right = m;
                    }
                }
                return ans - left;
            }
        }
    }
    
}

class Utilities {
    static String arrayToLineString(Object[] arr) {
        return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n"));
    }
    
    static String arrayToLineString(int[] arr) {
        return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new));
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public int[] nextIntArray() throws Exception {
        return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}