General Payne has a battalion of *n* soldiers. The soldiers' beauty contest is coming up, it will last for *k* days. Payne decided that his battalion will participate in the pageant. Now he has choose the participants.

All soldiers in the battalion have different beauty that is represented by a positive integer. The value *a*<sub class="lower-index">*i*</sub> represents the beauty of the *i*-th soldier.

On each of *k* days Generals has to send a detachment of soldiers to the pageant. The beauty of the detachment is the sum of the beauties of the soldiers, who are part of this detachment. Payne wants to surprise the jury of the beauty pageant, so each of *k* days the beauty of the sent detachment should be unique. In other words, all *k* beauties of the sent detachments must be distinct numbers.

Help Payne choose *k* detachments of different beauties for the pageant. Please note that Payne cannot just forget to send soldiers on one day, that is, the detachment of soldiers he sends to the pageant should never be empty.
The first line contains two integers *n*, *k* (1 ≤ *n* ≤ 50; 1 ≤ *k* ≤  <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/5e54199c623e6698508e30637903d25ae30f0d42.png" style="max-width: 100.0%;max-height: 100.0%;"/>) — the number of soldiers and the number of days in the pageant, correspondingly. The second line contains space-separated integers *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> (1 ≤ *a*<sub class="lower-index">*i*</sub> ≤ 10<sup class="upper-index">7</sup>) — the beauties of the battalion soldiers.

It is guaranteed that Payne's battalion doesn't have two soldiers with the same beauty.
import sys
input = sys.stdin.readline
from itertools import combinations

n, k = map(int, input().split())
w = list(map(int, input().split()))
t = 0
d = dict()
while 1:
    t += 1
    for i in list(combinations(list(range(1, n+1)), t)):
        x = [w[j-1] for j in i]
        c = sum(x)
        if c not in d:
            d[c] = 1
            k -= 1
            print(t, *x)
            if k == 0:
                exit()