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 Java (OpenJDK 11.0.6) (judge verdict: Wrong Answer)

import java.util.*;

class Main
{
    public static void main (String[] args)
    {
        Scanner sc = new Scanner (System.in);
        
        int x = sc.nextInt();
        int n = sc.nextInt();
        int[] array = new int[n];
        for (int i = 0; i < n; i++) {
            array[i] = sc.nextInt();
        }
        
        //もしゼロだったら答えを返して終わり
        if (n == 0) {
            System.out.println(x);   
            return;
        }
        //nがゼロ以外だったら
        Arrays.sort(array);
        int abs = 100;
        int num = 0;
        for (int i = 0; i <= 100; i++) {
            int count = 0;
            for (int j = 0; j < n; j++) {
                if (i == array[j]) {
                    count++;
                }
            }
            if (count == 0) {

            //数字間の大きさを比較して絶対値を求める
            //もし絶対値が増加したらリターン
            if (i < x) {
                int dif = x - i;
                if (dif < abs) {
                    abs = dif;
                    num = i;
                } else {

                    break;
                }
            } else if (i > x) {
                int dif = i - x;
                if (dif < abs) {
                    abs = dif;
                    num = i;
                } else {

                    break;
                }
            } else if (i == x) {

                break;
            }
            }
        }
        System.out.println(num);
    }
}