n,*a=map(int,open(0).read().split())
if n<2:print(1);exit()
i=l=y=0
while i<n-1:
 g=a[i]
 if(g-a[i-1])^(a[i+1]-g):l=max(l,i-y);y=i
 i+=1
print(max(l+1,n-y))