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: Accepted)

import sys
#sys.exit()
#sorted( ,reverse=True)
#N = int(input())
X, N = map(int, input().split())
P = list(map(int, input().split()))


if N ==0:
    print(X)
    sys.exit()
    
if X not in P:
    print(X)
    sys.exit()
cnt= 1
while True:
    #print(X-cnt,X+cnt)
    if (X -cnt) not in P:
        print(X-cnt)
        sys.exit()
    elif (X+cnt) not in P:
        print(X+cnt)
        sys.exit()
    cnt += 1  

#A = [int(input()) for _ in range(N)]

#cnt = 0
#cnt += 1



#print(N)
#print(S,T)
#print(A)
#print('Yes')
#print('No')
#print(cnt)