class UnionFind:
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n
        self.group = n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return
        self.group -= 1
        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return self.group

    def all_group_members(self):
        dic = {r:[] for r in self.roots()}
        for i in range(self.n):
            dic[self.find(i)].append(i)
        return dic

    def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots())

n = int(input())
lst = []
xy = [list(map(int, input().split())) for _ in range(n)]
for i in range(n):
    for j in range(i + 1, n):
        dx = xy[j][0] - xy[i][0]
        dy = xy[j][1] - xy[i][1]
        d2 = dx ** 2 + dy ** 2
        lst.append(d2 * (n * n) + i * n + j)

lst.sort()
UF = UnionFind(n)
for dij in lst:
    d = dij // (n * n)
    dij -= d * n * n
    i = dij // n
    j = dij - i * n
    UF.union(i, j)
    if UF.same(0, n - 1):
        break

x = int(d ** 0.5)
x = (x + 9) // 10 * 10
while x * x > d:
    x -= 10
while x * x < d:
    x += 10

print(x)