Create 46-Permutations.py

Author: neetcode-gh

46-Permutations.py

@@ -0,0 +1,17 @@
+class Solution:
+    def permute(self, nums: List[int]) -> List[List[int]]:
+        res = []
+        
+        # base case
+        if len(nums) == 1:
+            return [nums[:]] # nums[:] is a deep copy
+        
+        for i in range(len(nums)):
+            n = nums.pop(0)
+            perms = self.permute(nums)
+            
+            for perm in perms:
+                perm.append(n)
+            res.extend(perms)
+            nums.append(n)
+        return res