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Python: Find the three elements that sum to zero from a set of n real numbers

Python Class: Exercise-6 with Solution

Write a Python class to find the three elements that sum to zero from a set (array) of n real numbers.

Sample Solution:

Python Code:

class py_solution:
 def threeSum(self, nums):
        nums, result, i = sorted(nums), [], 0
        while i < len(nums) - 2:
            j, k = i + 1, len(nums) - 1
            while j < k:
                if nums[i] + nums[j] + nums[k] < 0:
                    j += 1
                elif nums[i] + nums[j] + nums[k] > 0:
                    k -= 1
                else:
                    result.append([nums[i], nums[j], nums[k]])
                    j, k = j + 1, k - 1
                    while j < k and nums[j] == nums[j - 1]:
                        j += 1
                    while j < k and nums[k] == nums[k + 1]:
                        k -= 1
            i += 1
            while i < len(nums) - 2 and nums[i] == nums[i - 1]:
                i += 1
        return result

print(py_solution().threeSum([-25, -10, -7, -3, 2, 4, 8, 10]))

Sample Output:

[[-10, 2, 8], [-7, -3, 10]] 

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Python: Find the three elements that sum to zero from a set of n real numbers.
Python: Find the three elements that sum to zero from a set of n real numbers.

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Flowchart: Find the three elements that sum to zero from a set of n real numbers

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Previous: Write a Python class to find a pair of elements (indices of the two numbers) from a given array whose sum equals a specific target number.
Next: Write a Python class to implement pow(x, n).

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Python: Tips of the Day

The Zip() Function:

>>> students = ('John', 'Mary', 'Mike')
>>> ages = (15, 17, 16)
>>> scores = (90, 88, 82, 17, 14)
>>> for student, age, score in zip(students, ages, scores):
...     print(f'{student}, age: {age}, score: {score}')
... 
John, age: 15, score: 90
Mary, age: 17, score: 88
Mike, age: 16, score: 82
>>> zipped = zip(students, ages, scores)
>>> a, b, c = zip(*zipped)
>>> print(b)
(15, 17, 16)