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 JavaScript (Node.js 12.16.1) (judge verdict: Wrong Answer)

fs = require('fs');
input = fs.readFileSync('/dev/stdin', 'utf8');
tmp = input.split('\n');
X = parseInt(tmp[0].split(' ')[0]);
N = parseInt(tmp[0].split(' ')[1]);
if(N == 0) { console.log(X); return; }
p = tmp[1].split(' ');
r = 0;
for(i=100; i>=1; i--) {
  f = true;
  for(j=0; j<p.length; j++) {
    if(parseInt(p[j],10) == i) { f = false; }
  }
  if(f == true) {
    if(Math.abs(i - X) <= Math.abs(r - X) || r == 0) r = i; }
}
console.log(r);