题目描述
Given are an integer X and an integer sequence of length N: $p_1, \ldots, p_N$.
Among the integers not contained in the sequence $p_1, \ldots, p_N ($not necessarily positive), find the integer nearest to X, that is, find the integer whose absolute difference with X is the minimum. If there are multiple such integers, report the smallest such integer.
Constraints
- $1 \leq X \leq 100$
- $0 \leq N \leq 100$
- $1 \leq p_i \leq 100$
- $p_1, \ldots, p_N$ are all distinct.
- All values in input are integers.
Input
Input is given from Standard Input in the following format:
X N
p_1 ... p_N
Output
Print the answer.
Examples
Input
6 5
4 7 10 6 5
Output
8
Input
10 5
4 7 10 6 5
Output
9
Input
100 0
Output
100
输入格式
见题面
输出格式
见题面
样例输入
6 5
4 7 10 6 5
样例输出
8