Solution two sum problem at leetcode

Author: luucamay

Diff for: leetcode-daily_interview_problem/two_sum.py

@@ -0,0 +1,28 @@
+'''
+Two Sum - Leetcode #1
+
+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, and you may not use the same element twice.
+
+Example:
+Given nums = [2, 7, 11, 15], target = 9,
+Because nums[0] + nums[1] = 2 + 7 = 9,
+return [0, 1].
+'''
+class Solution(object):
+    def twoSum(self, nums, target):
+        """
+        :type nums: List[int]
+        :type target: int
+        :rtype: List[int]
+        """
+        map_nums = {}
+        n = len(nums)
+        for j in range(n):
+            map_nums[nums[j]] = j
+        for i in range(n):
+            comp = target - nums[i]
+            if comp in map_nums and i != map_nums[comp]:
+                return [i, map_nums[comp]]
+        return []
+