import java.util.*;

public class Main {
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Point[] points = new Point[n];
		for (int i = 0; i < n; i++) {
		    points[i] = new Point(sc.nextInt(), sc.nextInt());
		}
		PriorityQueue<Path> queue = new PriorityQueue<>();
		queue.add(new Path(0,0));
		long[] costs = new long[n];
		Arrays.fill(costs, Long.MAX_VALUE);
		while (queue.size() > 0) {
		    Path p = queue.poll();
		    if (costs[p.idx] <= p.value) {
		        continue;
		    }
		    costs[p.idx] = p.value;
		    for (int i = 0; i < n; i++) {
		        if (costs[i] == Long.MAX_VALUE) {
		            queue.add(new Path(i, Math.max(p.value, points[p.idx].getDistance(points[i]))));
		        }
		    }
		}
		long left = 0;
		long right = Integer.MAX_VALUE;
		while (right - left > 1) {
		    long m = (left + right) / 2;
		    if (m * m >= costs[n - 1]) {
		        right = m;
		    } else {
		        left = m;
		    }
		}
		long ans = (right + 9) / 10 * 10;
		System.out.println(ans);
	}
	
	static class Path implements Comparable<Path> {
	    int idx;
	    long value;
	    
	    public Path(int idx, long value) {
	        this.idx = idx;
	        this.value = value;
	    }
	    
	    public int compareTo(Path another) {
	        if (value == another.value) {
	            return 0;
	        } else if (value > another.value) {
	            return 1;
	        } else {
	            return -1;
	        }
	    }
	}
	
	static class Point {
	    int x;
	    int y;
	    
	    public Point(int x, int y) {
	        this.x = x;
	        this.y = y;
	    }
	    
	    public long getDistance(Point another) {
	        return (long)(x - another.x) * (x - another.x) + (long)(y - another.y) * (y - another.y);
	    }
	}
}