n,k=map(int,input().split()) l1=list(map(int,input().split())) def suShu(n): f=True for i in range(2,n): if n%i==0: f=True else: f=False return f l1.sort(reverse = True) #从大到小排列 a=l1[k-1] l1.sort() #从小到大排列 b=l1[k-1] if suShu(a-b): print('YES') print(a-b) else: print('NO') print(a-b) /************************************************************** Problem: 1242 User: admin Language: Python Result: Accepted Time:98 ms Memory:34480 kb ****************************************************************/