Leetcode Three Sum in Python
$begingroup$
Here's my solution for the Leet Code's Two Sum problem -- would love feedback on (1) code efficiency and (2) style/formatting.
Problem:
Given an array nums of n integers, are there elements a, b, c in nums
such that a + b + c = 0? Find all unique triplets in the array which
gives the sum of zero.
Note:
The solution set must not contain duplicate triplets.
Example:
Given array nums = [-1, 0, 1, 2, -1, -4],
A solution set is: [ [-1, 0, 1], [-1, -1, 2] ]
My solution:
def threeSum(nums):
"""
:type nums: List[int]
:rtype: List[List[int]]
"""
def _twoSum(nums_small, target):
'''
INPUT: List of numeric values, int target
OUTPUT: list: pair(s) from nums_small that add up to target and -1*target
'''
nums_dict = {}
return_lst =
for indx, val in enumerate(nums_small, target):
if target - val in nums_dict:
return_lst.append([val, target - val, -1*target])
nums_dict[val] = indx
return return_lst
return_dict = {}
for indx, val in enumerate(nums):
for solution in _twoSum(nums[:indx] + nums[indx+1:], -1*val):
if sorted(solution) not in return_dict.values():
return_dict[str(indx)+str(solution)] = sorted(solution) # ... hacky way of storing multiple solutions to one index ...
return list(return_dict.values())
python
asked 18 mins ago
zthomas.nczthomas.nc
263311
$endgroup$
add a comment |
$begingroup$
Here's my solution for the Leet Code's Two Sum problem -- would love feedback on (1) code efficiency and (2) style/formatting.
Problem:
Given an array nums of n integers, are there elements a, b, c in nums
such that a + b + c = 0? Find all unique triplets in the array which
gives the sum of zero.
Note:
The solution set must not contain duplicate triplets.
Example:
Given array nums = [-1, 0, 1, 2, -1, -4],
A solution set is: [ [-1, 0, 1], [-1, -1, 2] ]
My solution:
def threeSum(nums):
"""
:type nums: List[int]
:rtype: List[List[int]]
"""
def _twoSum(nums_small, target):
'''
INPUT: List of numeric values, int target
OUTPUT: list: pair(s) from nums_small that add up to target and -1*target
'''
nums_dict = {}
return_lst =
for indx, val in enumerate(nums_small, target):
if target - val in nums_dict:
return_lst.append([val, target - val, -1*target])
nums_dict[val] = indx
return return_lst
return_dict = {}
for indx, val in enumerate(nums):
for solution in _twoSum(nums[:indx] + nums[indx+1:], -1*val):
if sorted(solution) not in return_dict.values():
return_dict[str(indx)+str(solution)] = sorted(solution) # ... hacky way of storing multiple solutions to one index ...
return list(return_dict.values())
python
asked 18 mins ago
zthomas.nczthomas.nc
263311
$endgroup$
add a comment |
$begingroup$
Here's my solution for the Leet Code's Two Sum problem -- would love feedback on (1) code efficiency and (2) style/formatting.
Problem:
Given an array nums of n integers, are there elements a, b, c in nums
such that a + b + c = 0? Find all unique triplets in the array which
gives the sum of zero.
Note:
The solution set must not contain duplicate triplets.
Example:
Given array nums = [-1, 0, 1, 2, -1, -4],
A solution set is: [ [-1, 0, 1], [-1, -1, 2] ]
My solution:
def threeSum(nums):
"""
:type nums: List[int]
:rtype: List[List[int]]
"""
def _twoSum(nums_small, target):
'''
INPUT: List of numeric values, int target
OUTPUT: list: pair(s) from nums_small that add up to target and -1*target
'''
nums_dict = {}
return_lst =
for indx, val in enumerate(nums_small, target):
if target - val in nums_dict:
return_lst.append([val, target - val, -1*target])
nums_dict[val] = indx
return return_lst
return_dict = {}
for indx, val in enumerate(nums):
for solution in _twoSum(nums[:indx] + nums[indx+1:], -1*val):
if sorted(solution) not in return_dict.values():
return_dict[str(indx)+str(solution)] = sorted(solution) # ... hacky way of storing multiple solutions to one index ...
return list(return_dict.values())
python
asked 18 mins ago
zthomas.nczthomas.nc
263311
$endgroup$
Here's my solution for the Leet Code's Two Sum problem -- would love feedback on (1) code efficiency and (2) style/formatting.
Problem:
Given an array nums of n integers, are there elements a, b, c in nums
such that a + b + c = 0? Find all unique triplets in the array which
gives the sum of zero.
Note:
The solution set must not contain duplicate triplets.
Example:
Given array nums = [-1, 0, 1, 2, -1, -4],
A solution set is: [ [-1, 0, 1], [-1, -1, 2] ]
My solution:
def threeSum(nums):
"""
:type nums: List[int]
:rtype: List[List[int]]
"""
def _twoSum(nums_small, target):
'''
INPUT: List of numeric values, int target
OUTPUT: list: pair(s) from nums_small that add up to target and -1*target
'''
nums_dict = {}
return_lst =
for indx, val in enumerate(nums_small, target):
if target - val in nums_dict:
return_lst.append([val, target - val, -1*target])
nums_dict[val] = indx
return return_lst
return_dict = {}
for indx, val in enumerate(nums):
for solution in _twoSum(nums[:indx] + nums[indx+1:], -1*val):
if sorted(solution) not in return_dict.values():
return_dict[str(indx)+str(solution)] = sorted(solution) # ... hacky way of storing multiple solutions to one index ...
return list(return_dict.values())
python
python
asked 18 mins ago
zthomas.nczthomas.nc
263311
asked 18 mins ago
zthomas.nczthomas.nc
263311
asked 18 mins ago
zthomas.nczthomas.nc
263311
asked 18 mins ago
zthomas.nczthomas.nc
263311
asked 18 mins ago
zthomas.nczthomas.nc
263311
263311
add a comment |
add a comment |
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