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 Fortran (GNU Fortran 9.2.1) (judge verdict: Wrong Answer)

program main
	implicit none
	integer(8):: N,i,j,t,K,X
	integer,dimension(1:100)::A,B,C
	read *, X,N
    read(*,*) (A(i), i = 1, N)
	t=0
	k=0
	do j=1,N
	do i=1,N
		if((A(i)-X+t)==0)then
			t=t+1
			exit
		end if
	end do
	do i=1,N
		if((A(i)-X-k)==0)then
			k=k+1
			exit
		end if
	end do
	end do

	if(t==0.and.k==0)		print'(I0)',X
	
	if (t>k)t=k
	
	do i=1,N
	
		if((A(i)-X+t)/=0)then
		print'(I0)',X-t
		stop
		end if
		if((A(i)-X-t)/=0)then
		print'(I0)',X+t
		stop
		end if
	end do
end program main