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.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String[] str1 = sc.nextLine().split(" ");
    String[] str2 = sc.nextLine().split(" ");
    int x = Integer.parseInt(str1[0]);
    int n = Integer.parseInt(str1[1]);
    if(n==0) {
        System.out.println(x);
    }
    else {
        List<String> list = new ArrayList<String>();
        for(int i = 0 ; i < 101;i++) {
          list.add((((Integer)i).toString()));
        }
        for(int i = 0 ; i < str2.length;i++) {
            list.remove (str2[i]);
        }
        int cnt=9999;
        int ansX=9999;
        for(String num2 : list) {
            int num = Integer.parseInt(num2);
            if(Math.abs(num-x) <=cnt) {
                if(cnt == Math.abs(num-x))break;
                cnt = Math.abs(num-x);
                ansX = num;
            }
        }
        System.out.println(ansX);
    }
  }
}