[leetcode] 1. two sum Code 1 (exhaustive search): Code 2:

Leetcode link for this question

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution.

Example:

Given nums = [2, 7, 11, 15], target = 9,

Because nums[0] + nums[1] = 2 + 7 = 9,
return [0, 1].

UPDATE (2016/2/13):

The return format had been changed to zero-based indices. Please read the above updated description carefully.

Code 1 (exhaustive search):

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class (object):
def twoSum(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: List[int]
"""
for i in range(len(nums)):
for j in range(i+1,len(nums)):
if nums[i]+nums[j]==target:
return[i,j]

Submission Result:

Status: Accepted
Runtime: 5872 ms
Ranking: beats 9.41%

Code 2:

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class (object):
def twoSum(self, nums, target):
"""
:type nums: List[int]
:type target: int
:rtype: List[int]
"""
tmp=[]
for i in range(len(nums)):
tmp.append((i,nums[i]))
tmp=sorted(tmp,key=lambda t:t[1])
nums.sort()
i=0
j=len(nums)-1
while i<=j:
if nums[i]+nums[j]<target:
i+=1
elif nums[i]+nums[j]>target:
j-=1
else:
return [tmp[i][0],tmp[j][0]]

Submission Result:

Status: Accepted
Runtime: 52 ms
Ranking: beats 73.69%