#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int,raw_input().strip().split(' '))


ans=0
i=0
for i in range(len(a)):
    if a[i]<0:
        a[i]*=-1
a.sort()

i=0
ans=0
while i<(len(a)-1):
    j=i+1
    x=0
    while a[j]-a[i]<=1 and j<len(a):
        x+=1
        if x>ans:
            ans=x
        j+=1
        if j==len(a):
            break
    i+=1        
print ans+1