Python Challenges: Find three numbers from an array such that the sum of three numbers equal to a given number

Python Challenges - 1: Exercise-10 with Solution

Write a Python program to find three numbers from an array such that the sum of three numbers equal to a given number.

Sample Solution:-

Python Code:

def four_Sum(nums, target):
        nums.sort()
        result = []
        for i in range(len(nums) - 3):
            if i and nums[i] == nums[i - 1]:
                continue
            for j in range(i + 1, len(nums) - 2):
                if j != i + 1 and nums[j] == nums[j - 1]:
                    continue
                sum = target - nums[i] - nums[j]
                left, right = j + 1, len(nums) - 1
                while left < right:
                    if nums[left] + nums[right] == sum:
                        result.append([nums[i], nums[j], nums[left], nums[right]])
                        right -= 1
                        left += 1
                        while left < right and nums[left] == nums[left - 1]:
                            left += 1
                        while left < right and nums[right] == nums[right + 1]:
                            right -= 1
                    elif nums[left] + nums[right] > sum:
                        right -= 1
                    else:
                        left += 1
        return result

print(four_Sum([1, 0, -1, 0, -2, 2], 0))

Sample Output:

[[-2, -1, 1, 2], [-2, 0, 0, 2], [-1, 0, 0, 1]]

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