BOJ15657 N과 M 8

import sys
sys.setrecursionlimit((10**5))

N, M = map(int, input().split())

elem = list(map(int, input().split()))
elem.sort()

check = [0] * N
ans = [0] * N

def recur(depth, start):
	if depth >= M:
		print(' '.join(map(str, ans[:M])))
		return
	
	for i in range(start, N):
		ans[depth] = elem[i]
		recur(depth+1, i)
recur(0, 0)