Buggy python submission (verdict: Runtime Error):

def s0():return input()
def s1():return input().split()
def s2(n):return [input() for x in range(n)]
def s3(n):return [input().split() for _ in range(n)]
def s4(n):return [[x for x in s] for s in s2(n)]
def n0():return int(input())
def n1():return [int(x) for x in input().split()]
def n2(n):return [int(input()) for _ in range(n)]
def n3(n):return [[int(x) for x in input().split()] for _ in range(n)]
def t3(n):return [tuple(int(x) for x in input().split()) for _ in range(n)]
def p0(b,yes="Yes",no="No"): print(yes if b else no)
# from sys import setrecursionlimit
# setrecursionlimit(1000000)
# from collections import Counter,deque,defaultdict
# import itertools
# import math
# import networkx as nx
# from bisect import bisect_left,bisect_right
# from heapq import heapify,heappush,heappop
x,n=n1()

if n==0:
    print(x)
else:
    P=n1()
    if (not x in P):
        print(x)
    else:
        d=[]
        d2=[]
        for i in range(1,101):
            if (not i in P):
                d.append(i)
                d2.append(abs(x-i))

        a=min(d2)
        if x-a in d:
            print(x-a)
        else:
            print(x+a)

Fixed submission:

def s0():return input()
def s1():return input().split()
def s2(n):return [input() for x in range(n)]
def s3(n):return [input().split() for _ in range(n)]
def s4(n):return [[x for x in s] for s in s2(n)]
def n0():return int(input())
def n1():return [int(x) for x in input().split()]
def n2(n):return [int(input()) for _ in range(n)]
def n3(n):return [[int(x) for x in input().split()] for _ in range(n)]
def t3(n):return [tuple(int(x) for x in input().split()) for _ in range(n)]
def p0(b,yes="Yes",no="No"): print(yes if b else no)
# from sys import setrecursionlimit
# setrecursionlimit(1000000)
# from collections import Counter,deque,defaultdict
# import itertools
# import math
# import networkx as nx
# from bisect import bisect_left,bisect_right
# from heapq import heapify,heappush,heappop
x,n=n1()

if n==0:
    print(x)
else:
    P=n1()
    if (not x in P):
        print(x)
    else:
        d=[]
        d2=[]
        for i in range(0,102):
            if (not i in P):
                d.append(i)
                d2.append(abs(x-i))

        a=min(d2)
        if (x-a) in d:
            print(x-a)
        else:
            print(x+a)

Buggy python submission (verdict: Runtime Error):

def s0():return input()
def s1():return input().split()
def s2(n):return [input() for x in range(n)]
def s3(n):return [input().split() for _ in range(n)]
def s4(n):return [[x for x in s] for s in s2(n)]
def n0():return int(input())
def n1():return [int(x) for x in input().split()]
def n2(n):return [int(input()) for _ in range(n)]
def n3(n):return [[int(x) for x in input().split()] for _ in range(n)]
def t3(n):return [tuple(int(x) for x in input().split()) for _ in range(n)]
def p0(b,yes="Yes",no="No"): print(yes if b else no)
# from sys import setrecursionlimit
# setrecursionlimit(1000000)
# from collections import Counter,deque,defaultdict
# import itertools
# import math
# import networkx as nx
# from bisect import bisect_left,bisect_right
# from heapq import heapify,heappush,heappop
x,n=n1()
P=n1()

if len(P)==0:
    print(x)
elif not x in P:
    print(x)
else:
    d=[]
    d2=[]
    for i in range(1,101):
        if not i in P:
            d.append(i)
            d2.append(abs(x-i))

    a=min(d2)
    if x-a in d:
        print(x-a)
    else:
        print(x+a)

Fixed submission:

def s0():return input()
def s1():return input().split()
def s2(n):return [input() for x in range(n)]
def s3(n):return [input().split() for _ in range(n)]
def s4(n):return [[x for x in s] for s in s2(n)]
def n0():return int(input())
def n1():return [int(x) for x in input().split()]
def n2(n):return [int(input()) for _ in range(n)]
def n3(n):return [[int(x) for x in input().split()] for _ in range(n)]
def t3(n):return [tuple(int(x) for x in input().split()) for _ in range(n)]
def p0(b,yes="Yes",no="No"): print(yes if b else no)
# from sys import setrecursionlimit
# setrecursionlimit(1000000)
# from collections import Counter,deque,defaultdict
# import itertools
# import math
# import networkx as nx
# from bisect import bisect_left,bisect_right
# from heapq import heapify,heappush,heappop
x,n=n1()

if n==0:
    print(x)
else:
    P=n1()
    if (not x in P):
        print(x)
    else:
        d=[]
        d2=[]
        for i in range(0,102):
            if (not i in P):
                d.append(i)
                d2.append(abs(x-i))

        a=min(d2)
        if (x-a) in d:
            print(x-a)
        else:
            print(x+a)