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 Python (3.8.2) (judge verdict: Wrong Answer)

n = input().split()
n = [int(i) for i in n]
if not n[1] == 0:
	m = input().split()
	m = [int(i) for i in m]
else:
  	m =[0]

ans_1 = n[0]
ans_2 = n[0]
ans = []
while True:
    if n[1] == 0:
        ans.append(n[0])
    if len(ans) > 0:
        break    
        
    ans_1 += 1
    ans_2 -= 1
    if not ans_1 in m:
        ans.append(ans_1)
    if not ans_2 in m:
        ans.append(ans_2)
    
    
        
print(min(ans))