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()); } ArrayList lines = new ArrayList<>(); for (int i = 0; i < n; i++) { for (int j = i + 1; j < n; j++) { lines.add(new Line(i, j, points[i].getDistance(points[j]))); } } Collections.sort(lines); UnionFindTree uft = new UnionFindTree(n); long ans = 0; for (Line x : lines) { uft.unite(x); ans = x.value; if (uft.same(0, n - 1)) { break; } } long left = 0; long right = Integer.MAX_VALUE / 10; while (right - left > 1) { long m = (left + right) / 2; if (m * m * 100 < ans) { left = m; } else { right = m; } } System.out.println(right * 10); } 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(Line x) { unite(x.left, x.right); } } static class Line implements Comparable { int left = 0; int right = 0; long value; public Line(int left, int right, long value) { this.left = left; this.right = right; this.value = value; } public int compareTo(Line another) { if (value == another.value) { return 0; } else if (value < another.value) { return -1; } else { return 1; } } } static class Point { long x; long y; public Point(long x, long y) { this.x = x; this.y = y; } public long getDistance(Point p) { return (x - p.x) * (x - p.x) + (y - p.y) * (y - p.y); } } } 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(); } }