4675: Collective Mindsets (medium)

内存限制:256 MB 时间限制:2 S
题面:传统 评测方式:文本比较 上传者:
提交:2 通过:2

题目描述

A2. Collective Mindsets (medium)
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output
Way to go! Heidi now knows how many brains there must be for her to get one. But throwing herself in the midst of a clutch of hungry zombies is quite a risky endeavor. Hence Heidi wonders: what is the smallest number of brains that must be in the chest for her to get out at all (possibly empty-handed, but alive)?
The brain dinner night will evolve just as in the previous subtask: the same crowd is present, the N-1 zombies have the exact same mindset as before and Heidi is to make the first proposal, which must be accepted by at least half of the attendees for her to survive.
Input
The only line of input contains one integer: N, the number of attendees (1≤N≤109).
Output
Output one integer: the smallest number of brains in the chest which allows Heidi to merely survive.
Examples
Input
1
Output
0
Input
3
Output
1
Input
99
Output
49

输入样例 复制


输出样例 复制


分类标签