import sys

sys.setrecursionlimit(10 ** 6)
from bisect import *
from collections import *
from heapq import *
import math

int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.readline())
def SI(): return sys.stdin.readline()[:-1]
def MI(): return map(int, sys.stdin.readline().split())
def MI1(): return map(int1, sys.stdin.readline().split())
def MF(): return map(float, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LF(): return list(map(float, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
dij = [(0, 1), (1, 0), (0, -1), (-1, 0)]

def main():
    def cald(d):
        s=max(math.ceil(d**0.5)//10*10-20,0)
        for x in range(s,s+100,10):
            if x**2>=d:return x


    n=II()
    xy=[]
    to=defaultdict(list)
    for i in range(n):
        x0,y0=MI()
        for j,(x,y) in enumerate(xy):
            d=(x0-x)**2+(y0-y)**2
            to[i].append((j,d))
            to[j].append((i,d))
        xy.append((x0,y0))
    fin=[False]*n
    hp=[]
    heappush(hp,[0,0])
    while hp:
        d,i=heappop(hp)
        if i==n-1:
            print(cald(d))
            exit()
        if fin[i]:continue
        fin[i]=True
        for j,c in to[i]:
            if fin[j]:continue
            heappush(hp,[max(d,c),j])

main()