201364: [AtCoder]ARC136 E - Non-coprime DAG

Memory Limit:1024 MB Time Limit:2 S
Judge Style:Text Compare Creator:
Submit:0 Solved:0

Description

Score : $800$ points

Problem Statement

We have a directed graph $G$ with $N$ vertices numbered $1$ to $N$.

Between two vertices $i,j$ ($1 \leq i,j \leq N$, $i \neq j$), there is an edge $i \to j$ if and only if both of the following conditions are satisfied.

  • $i<j$
  • $\mathrm{gcd}(i,j)>1$

Additionally, each vertex has an associated value: the value of Vertex $i$ is $A_i$.

Consider choosing a set $s$ of vertices so that the following condition is satisfied.

  • For every pair $(x,y)$ ($x<y$) of different vertices in $s$, $y$ is unreachable from $x$ in $G$.

Find the maximum possible total value of vertices in $s$.

Constraints

  • $1 \leq N \leq 10^6$
  • $1 \leq A_i \leq 10^9$
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

$N$
$A_1$ $A_2$ $\cdots$ $A_N$

Output

Print the answer.


Sample Input 1

6
1 1 1 1 1 1

Sample Output 1

4

We should choose $s=\{1,2,3,5\}$.


Sample Input 2

6
1 2 1 3 1 6

Sample Output 2

8

We should choose $s=\{1,5,6\}$.


Sample Input 3

20
40 39 31 54 27 31 80 3 62 66 15 72 21 38 74 49 15 24 44 3

Sample Output 3

343

Input

题意翻译

构造一个图,$(i,j)$ 有边当且仅当 $i<j$ 且 $(i,j)>1$,求一个反链 $S$,使得 $\sum\limits_{i\in S}A_i$ 最大。 translated by syzf2222

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