def combination_dfs(n, k):
results = []
def dfs(elements, start, k):
print(elements)
if(k == 0):
results.append(elements[:])
return
for i in range(start, n + 1):
elements.append(i)
dfs(elements, i + 1, k - 1)
elements.pop()
dfs([], 1, k)
return results
import itertools
def combination_lib(n,k):
return list(itertools.combinations(range(1, n + 1), k))