﻿ Python: Find three numbers from an array such that the sum of three numbers equal to zero - w3resource

# 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:

```# 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))```

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