|
|
@@ -0,0 +1,20 @@
|
|
|
+# Given a set of distinct integers, nums, return all possible subsets.
|
|
|
+# This could be solved with backtrack algorithm.
|
|
|
+# Time complexity: O(1). Only list is appended (in Python. Because Python allocates
|
|
|
+# up to twice of the space as needed)
|
|
|
+# Space complexity: O(n^2). Store all the combination of a list with length n
|
|
|
+import pytest
|
|
|
+
|
|
|
+def test_subsets():
|
|
|
+ assert subsets([0,1]) == [[],[0],[0,1],[1]]
|
|
|
+
|
|
|
+def subsets(nums):
|
|
|
+ def backtrack(list, temp_list, nums,start):
|
|
|
+ list.append(temp_list)
|
|
|
+ for i in range(start,len(nums)):
|
|
|
+ backtrack(list,temp_list+[nums[i]],nums,i+1)
|
|
|
+ return list
|
|
|
+
|
|
|
+ list = []
|
|
|
+ backtrack(list,[],nums,0)
|
|
|
+ return list
|
