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>
#include <stdlib.h>

int main(){
    int x,n,i,y,z,t=0,p=0;
    char str[100][3];
    int a[100];
    scanf("%d %d",&x,&n);
    for(i=0;i<n;i++){
    scanf("%s",str[i]);
    }
    for(i=0;i<n;i++){
        *(a+i)=atoi(str[i]);
    }
        y=x;
        z=x;
    //for(i=0;i<n;i++){
    //    scanf("%d",&a[i]);
    //}
    if(y==0){
        printf("%d",x);
    }else{
        while(1){
            y--;
            z++;
            for(i=0;i<n;i++){
                if(y==a[i]){
                    t=1;
                    break;
                }
            }
            if(t==0){
                printf("%d\n",y);
                break;
            }
            for(i=0;i<n;i++){
                if(z==a[i]){
                    p=1;
                    break;
                }
            }
            if(p==0){
                printf("%d\n",z);
                break;
            }              
        }
       
    }

    return 0;
}