#include<iostream>
#include<fstream>
#include<iomanip>
#include<algorithm>
#include<map>
#include<cmath>
#include<cstring>
#include<string>
#include<queue>
#include<stack>
#include<cstdio>
#include<cstdlib>
using namespace std;
int n,k,sum,a,br[1024],m,used[1024];
void solveitnow ()
{
    int i;
    for (i=1;i<=m;i++)
    {
        if (used[i]==br[i])continue;

        //if
    }
}
int main ()
{
    int i,j,l=0,a;
    scanf("%d%d",&n,&k);
    for (i=0;i<n;i++)
    {
        scanf("%d",&a);
        if (a==k)l=1;
        br[a]++;
        m=max(m,a);
    }
    if (l==1){cout<<k<<endl;return 0;}


    solveitnow();
    cout<<k-1<<endl;
    //for (i=0;i<=m;i++)cout<<br[i]<<" ";cout<<endl;



    return 0;
}

/*

10 12
4 10 8 5 15 5 3 1 5 6
*/
