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 Scala (2.13.1) (judge verdict: Runtime Error)

object Main extends App {
    val tempList: Seq[Seq[String]] = {
      for (line <- io.Source.stdin.getLines()) yield {
        line.split(' ').toSeq
      }
    }.toSeq
    val X: Int = tempList(0)(0).toInt
    val N: Int = tempList(0)(1).toInt
    
    val numList: Seq[Int] = tempList(1).map(_.toInt)

    val minOfNumList: Int = numList.min
    val maxOfNumList: Int = numList.max
    
    //値がこの範囲外
    

    val rangeMinMax: Set[Int] = Range(minOfNumList, maxOfNumList).toList.toSet
    val diffRange: Set[Int] = rangeMinMax.diff(numList.toSet)

    val diffList: Seq[Int] = diffRange.toList
    val diffAbsList: Seq[Int] = diffList.map(x => (x-X).abs)
    val minIndex: Int = diffAbsList.indexOf(diffAbsList.min)
    val minOfDiffList: Int = diffList(minIndex)


    println(minOfDiffList)
}