permutation

from LeetCode

Author: SanjarH

list_permutation.py

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+# Learn Python together
+""" Given an array nums of distinct integers, return all the possible permutations. """
+
+# Solution 1 using loop and recursive
+
+def permute(nums):
+    if len(nums)<=1:
+        return [nums]
+    result= [] # empty list
+    # iteration through each item in the list
+    for i in range(len(nums)):
+        lis = nums[i]  # giving value at index i in lis variable
+        new_list = nums[:i]+nums[i+1:] # giving in new list all elemts of the list exclude lis
+        for perm in permute(new_list): # recursive call function for creating permutation
+            result.append([lis]+perm) # add variables to result
+    return result
+
+#check 
+list1 = [1,2,3]
+list2 = [0]
+print(permute(list1)) 
+# Output -> [[1, 2, 3], [1, 3, 2], [2, 1, 3], [2, 3, 1], [3, 1, 2], [3, 2, 1]]
+print(permute(list2))
+# Output -> [[0]]
+
+
+# Solution 2 using itertools library with tuples in the list
+from itertools import permutations
+
+def perm_tools(nums):
+    return list(permutations(nums))
+
+# check
+print(perm_tools(list1))
+# Output -> [(1, 2, 3), (1, 3, 2), (2, 1, 3), (2, 3, 1), (3, 1, 2), (3, 2, 1)]
+print(perm_tools(list2))
+# Output -> [(0,)]