import heapq n = int(input()) xy_ls = [tuple(map(int, input().split())) for i in range(n)] def sq_dist(xy1, xy2): x1, y1 = xy1 x2, y2 = xy2 return (x2 - x1)**2 + (y2 - y1)**2 sq_dist_ls = [] for i in range(n - 1): xy1 = xy_ls[i] for j in range(i + 1, n): xy2 = xy_ls[j] heapq.heappush(sq_dist_ls, (sq_dist(xy1, xy2), i, j)) def p_find(memo, p): if memo[p] < 0: return p memo[p] = p_find(memo, memo[p]) return memo[p] def p_union(memo, p1, p2): p1_root = p_find(memo, p1) p2_root = p_find(memo, p2) if p1_root != p2_root: memo[p1_root] = p2_root def get_ans(sq_x): x = int(sq_x**0.5 // 10 * 10) return x + 10 if x**2 < sq_x else x start = 0 goal = n - 1 memo = [-1] * n while len(sq_dist_ls) > 0: sq_dist, p1, p2 = heapq.heappop(sq_dist_ls) p_union(memo, p1, p2) if p_find(memo, start) == p_find(memo, goal): break ans = get_ans(sq_dist) print(ans)