Problem:
Score : 300 points

Problem Statement

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.

Sample Input 1

6 5
4 7 10 6 5

Sample Output 1

8

Among the integers not contained in the sequence 4, 7, 10, 6, 5, the one nearest to 6 is 8.

Sample Input 2

10 5
4 7 10 6 5

Sample Output 2

9

Among the integers not contained in the sequence 4, 7, 10, 6, 5, the ones nearest to 10 are 9 and 11. We should print the smaller one, 9.

Sample Input 3

100 0

Sample Output 3

100

When N = 0, the second line in the input will be empty. Also, as seen here, X itself can be the answer.

Solution in Kotlin (1.3.71) (judge verdict: Accepted)

import java.util.*

fun main(args: Array<String>) {
    val scan = Scanner(System.`in`)

    var (x,n) = scan.nextLine().split(" ").map{ it.trim().toInt() }.toTypedArray()
    if(n==0)
        println(x)


    else {
        var arr = scan.nextLine().split(" ").map{ it.trim().toInt() }.toTypedArray()
        var p = x
        while (true) {
            if (!arr.contains(p))
                break
            else
                p++
        }
        var q = x
        while (true) {
            if (!arr.contains(q))
                break
            else
                q--
        }
        var s1 = Math.abs(p - x)
        var s2 = Math.abs(q - x)
        var ans = Math.min(s1, s2)
        if (ans == s2)
            println(q)
        else
            println(p)
    }
}