As you must know, the maximum clique problem in an arbitrary graph is NP -hard. Nevertheless, for some graphs of specific kinds it can be solved effectively. Just in case, let us remind you that a clique in a non-directed graph is a subset of the vertices of a graph, such that any two vertices of this subset are connected by an edge. In particular, an empty set of vertexes and a set consisting of a single vertex, are cliques. Let's define a divisibility graph for a set of positive integers A = {a 1, a 2, ..., a n } as follows. The vertices of the given graph are numbers from set A , and two numbers a i and a j ( i ≠ j ) are connected by an edge if and only if either a i is divisible by a j , or a j is divisible by a i . You are given a set of non-negative integers A . Determine the size of a maximum clique in a divisibility graph for set A .
输入描述:
The first line contains integer n (1 ≤ n ≤ 106), that sets the size of set A.The second line contains n distinct positive integers a1, a2, ..., an (1 ≤ ai ≤ 106) — elements of subset A. The numbers in the line follow in the ascending order.


输出描述:
Print a single number — the maximum size of a clique in a divisibility graph for set A.
示例1

输入

8<br />3 4 6 8 10 18 21 24<br />

输出

3<br />

备注:
In the first sample test a clique of size 3 is, for example, a subset of vertexes {3, 6, 18}. A clique of a larger size doesn't exist in this graph.
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