MEX.txt

import java.util.*;
class Main{

public static void main(String args[])
{   Scanner sc=new Scanner(System.in);
   int n=sc.nextInt();
   int k=sc.nextInt();
    int a[]=new int[n];
    for(int i=0;i<n;i++)
    a[i]=sc.nextInt();
    int ar[]=new int[k];
    int count=0;
    int arrval=0;
    int ans=-1;
    int start=0,end=0;
    while(end<n)
    {
        if(a[end]<k )
        {
            if(ar[a[end]]==0)
            count++;
            ar[a[end]]++;
            arrval++;
        }
        while(count==k)
        {
            if(ans==-1 || ans>(end-start+1))
            {
                if(arrval!=(end-start+1))
                ans=end-start+1;
            }
            if(a[start]<k)
                {
                ar[a[start]]--;
                if(ar[a[start]]==0)
                count--;
                arrval--;
                }
                start++;
        }
        end++;
    }
    System.out.println(ans);
    
}
}