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 C (GCC 9.2.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int main(){
	int x, n;
    int num[n];
    int i, j;
  	
  	scanf("%d", &x);
  	scanf("%d", &n);
  	for (i = 0; i < n; i++){
    	scanf("%d", &num[i]);
    }
  
  	for (i = 0; i < 100; i++){
    	for (j = 0; j < n; j++){
        	if((x - i) == num[j]){
            	break;
            }
        }
      	if (j == (n - 1)){
        	printf("%d", x - j);
            break;
        }
        for (j = 0; j < n; j++){
        	if((x + i) == num[j]){
            	break;
            }
        }
        if (j == (n - 1)){
            printf("%d", x - j);
            break;
        }
    }
}