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 PyPy3 (7.3.0) (judge verdict: Runtime Error)

from collections import defaultdict
X, N = map(int, input().split())
num = list(map(int, input().split()))

if N == 0:
    print(X)
else:
    num_list = [i for i in range(1, 101)]

    for i in range(X-1,-1,-1):
        if i in num:
            continue
        else:
            index1 = i
            break
            
    for i in range(X, 100):
        if i in num:
            continue
        else:
            index2 = i
            break
            
    if abs(X - index1) > abs(X - index2):
        print(index2)
    else:
        print(index1)