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: Runtime Error)

a = input().split()
b = int(a[0])
c = int(a[1])
d = [int(i) for i in input().split()]
e = sorted(d)


f = int(e[0]-1)
g = int(e[-1]+1)


h = int(g-f)

X = []
for I in range(int(h+1)):
    J = int(f+I)
    if e.count(J) == 0:
        X.append(J)

Y = len(X)
H = []
for S in range(Y):
    Q = X[S]
    if Q>=b:
        g = Q-b
        H.append(g)
    else:
        g = b-Q
        H.append(g)
P = sorted(H)
F = P[0]
O = H.index(F)
print(X[O])