add find triplets with 0 sum (3sum) (#10040)

* add find triplets with 0 sum (3sum)

* Update find_triplets_with_0_sum.py

* Update find_triplets_with_0_sum.py

---------

Co-authored-by: Christian Clauss <cclauss@me.com>

data_structures/arrays/find_triplets_with_0_sum.py

@@ -0,0 +1,24 @@
+from itertools import combinations
+
+
+def find_triplets_with_0_sum(nums: list[int]) -> list[list[int]]:
+    """
+    Given a list of integers, return elements a, b, c such that a + b + c = 0.
+    Args:
+        nums: list of integers
+    Returns:
+        list of lists of integers where sum(each_list) == 0
+    Examples:
+        >>> find_triplets_with_0_sum([-1, 0, 1, 2, -1, -4])
+        [[-1, -1, 2], [-1, 0, 1]]
+        >>> find_triplets_with_0_sum([])
+        []
+        >>> find_triplets_with_0_sum([0, 0, 0])
+        [[0, 0, 0]]
+        >>> find_triplets_with_0_sum([1, 2, 3, 0, -1, -2, -3])
+        [[-3, 0, 3], [-3, 1, 2], [-2, -1, 3], [-2, 0, 2], [-1, 0, 1]]
+    """
+    return [
+        list(x)
+        for x in sorted({abc for abc in combinations(sorted(nums), 3) if not sum(abc)})
+    ]