201470: [AtCoder]ARC147 A - Max Mod Min

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

Description

Score : $300$ points

Problem Statement

You are given a sequence of $N$ positive integers: $A=(A_1,A_2,\dots,A_N)$.

You will repeat the following operation until the length of $A$ becomes $1$.

  • Let $k$ be the length of $A$ before this operation. Choose integers $i$ and $j$ such that $\max(\{A_1,A_2,\dots,A_{k}\})=A_i,\min(\{A_1,A_2,\dots,A_{k}\})=A_j$, and $i \neq j$. Then, replace $A_i$ with $(A_i \bmod A_j)$. If $A_i$ becomes $0$ at this moment, delete $A_i$ from $A$.

Find the number of operations that you will perform. We can prove that, no matter how you choose $i,j$ in the operations, the total number of operations does not change.

Constraints

  • $2 \le N \le 2 \times 10^5$
  • $1 \le A_i \le 10^9$
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

$N$
$A_1$ $A_2$ $\dots$ $A_N$

Output

Print the answer.


Sample Input 1

3
2 3 6

Sample Output 1

3

You will perform $3$ operations as follows:

  • Choose $i=3,j=1$. You get $A_3=0$, and delete $A_3$ from $A$. Now you have $A=(2,3)$.
  • Choose $i=2,j=1$. You get $A_2=1$. Now you have $A=(2,1)$.
  • Choose $i=1,j=2$. You get $A_1=0$, and delete $A_1$ from $A$. Now you have $A=(1)$, and terminate the process because the length of $A$ becomes $1$.

Sample Input 2

6
1232 452 23491 34099 57341 21488

Sample Output 2

12

Input

题意翻译

有一个长度为$n$的正整数序列$A=(A_1,A_2,...,A_N)$。 重复以下操作直到序列$A$的长度变为$1$。 * 设$k$为操作前序列$A$的长度.选择整数$i$和$j$,使$A_i$为序列$A$中的最大值,$A_j$为序列$A$中的最小值,且$i≠j$。然后,用$(A_i \bmod A_j)$替换$A_i$。如果$A_i$的值在操作后变为$0$,从序列$A$中删除$A_i$. 请求出需要执行的操作的数量。我们可以证明,在操作中无论如何选择$i,j$,操作的总数是不变的

加入题单

算法标签: