47. Permutations II (Medium Level)

 

def dfs(nums, n, skip, perm, res):         if len(perm) == n:             res.add(tuple(perm[:]))             return         for i in range(n):             if skip[i] == True:                 continue             skip[i] = True             perm += nums[i],             dfs(nums, n, skip, perm, res)             perm.pop()             skip[i] = False     n = len(nums)     res = set()     dfs(nums, n, [False]*n, [], res)     return list(res)