#https://leetcode.com/problems/two-sum/

"""

when we iterate through the nums

we don't know if the counter part exist

so we store the counter part we want in the 'wanted' with the index now

so inside the wanted is {the_counter_part_we_want:index_now} [0]

later on if we found the num is in 'wanted'

we return the index_now and the index_now we previously stored in the 'wanted' [1]

"""

class Solution(object):

def twoSum(self, nums, target):

wanted = {}

for i in xrange(len(nums)):

n = nums[i]

if n in wanted: #[1]

return [wanted[n], i]

else:

wanted[target-n] = i #[0]

return []