#include<bits/stdc++.h>
using namespace std;
int main()
{
	int n,i,j=0,m,k,l=0;
	cin>>n;
	cin>>k;
	int h[10000];
	for(i=0;i<n;i++){
		cin>>h[i];
	} 
	for(i=1;i<=n-1;i++){
		for(j=1;j<=n-i;j++){
			if(h[j-1]<h[j]){
				swap(h[j-1],h[j]);
			}
		}
	}
	k--;
	m=h[k]-h[n-1-k];
	for(i=2;i<m;i++){
		if(m%i==0){
			l++;
		}
	}
	if(l==1){
		cout<<"NO"<<endl;
	}else{
		cout<<"YES"<<endl;
	}
	cout<<m;
	return 0;
}
/**************************************************************
	Problem: 1242
	User: zzz
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/