题库练习 Divisor Subtraction
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A12227 | Divisor Subtraction

时间限制1s
内存限制256MB
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题目描述

You are given an integer number $n$ . The following algorithm is applied to it:

1. if $n = 0$ , then end algorithm;
2. find the smallest prime divisor $d$ of $n$ ;
3. subtract $d$ from $n$ and go to step $1$ .

Determine the number of subtrations the algorithm will make.

输入格式

The only line contains a single integer $n$ ( $2 \le n \le 10^{10}$ ).

输出格式

Print a single integer — the number of subtractions the algorithm will make.

输入输出样例

输入 #1
5
输出 #1
1
输入 #2
4
输出 #2
2
C++ 编辑器
输入
输出