def g(check):
for i in check:
print(i,end=" ")
print()
def dfs(k,prev):
global m,L,check
if k == m-1:
for i in range(prev,len(L)):
check[k] = L[i]
g(check)
else:
for i in range(prev,len(L)):
check[k] = L[i]
dfs(k+1,i)
n,m = map(int,input().split())
L = list(set(list(map(int,input().split()))))
L.sort()
check = [0]*m
dfs(0,0)