# 0-indexed binary indexed tree class BIT: def __init__(self, n): self.n = n self.data = [0]*(n+1) self.el = [0]*(n+1) # sum of [0,i) sum(a[:i]) def sum(self, i): if i==0:return 0 s = 0 while i > 0: s += self.data[i] i -= i & -i return s def add(self, i, x): i+=1 self.el[i] += x while i <= self.n: self.data[i] += x i += i & -i # sum of [l,r) sum(a[l:r]) def sumlr(self, i, j): return self.sum(j) - self.sum(i) # a[i] def get(self,i): i+=1 return self.el[i] n=int(input()) a=list(map(int,input().split())) bit=BIT(n+1) ans=0 for x in a[::-1]: ans=max(ans,bit.sum(x)) bit.add(x,1) print(ans)