# Python, developed locally works, but doesn't work on LeetCode

• I'm trying to do a LeetCode question:

Given an array of integers, find two numbers such that they add up to
a specific target number.

The function twoSum should return indices of the two numbers such that
they add up to the target, where index1 must be less than index2.
not zero-based.

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

Input: numbers={2, 7, 11, 15}, target=9 Output: index1=1, index2=2

The first try was using two for loops, which gave me O(n^2), and unfortunately it didn't pass. Hence I tried to use:

``````target - current = index
``````

And search for if the index does exists on a dictionary.

This is my code:

``````class Solution:
def twoSum(self, nums, target):
dic = {}

#A number can appear twice inside the same index, so I use a list
for i in xrange(0, len(nums)):
try:
dic[nums[i]].append(i)
except:
dic[nums[i]] = []
dic[nums[i]].append(i)

try:
for items_1 in dic[nums[i]]:
for items_2 in dic[target-nums[i]]:
if(items_1+1 != items_2+1):
l = []
if(items_2+1 > items_1+1):
l.append(items_1+1)
l.append(items_2+1)
else:
l.append(items_2+1)
l.append(items_1+1)
return l
except:
pass
``````

I developed this locally, and I was able get the correct result with one of the test case that LeetCode was complaining: [-3,4,3,90], 0

The output I got was [1, 3], but on LeetCode it returned null, does anybody know why this would happen?

Looks like your connection to LeetCode Discuss was lost, please wait while we try to reconnect.