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

Python Challenges - 1: Exercise-9 with Solution

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

Explanation:

Sample Solution:

Python Code:

# return a list of lists of length 3 
def three_Sum(num):
    if len(num)<3: return []
    num.sort()
    result=[]
    for i in range(len(num)-2):
        left=i+1
        right=len(num)-1
        if i!=0 and num[i]==num[i-1]:continue
        while left<right:
            if num[left]+num[right]==-num[i]:
                result.append([num[i],num[left],num[right]])
                left=left+1
                right=right-1
                while num[left]==num[left-1] and left<right:left=left+1
                while num[right]==num[right+1] and left<right: right=right-1
            elif num[left]+num[right]<-num[i]:
                left=left+1
            else:
                right=right-1
    return result
 
nums1=[-1,0,1,2,-1,-4]
nums2 = [-25,-10,-7,-3,2,4,8,10]
print(three_Sum(nums1))
print(three_Sum(nums2))

Sample Output:

[[-1, -1, 2], [-1, 0, 1]]                                                                                     
[[-10, 2, 8], [-7, -3, 10]] 

Flowchart:

Python Code Editor:

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