two-sum solution

Author: devyejin

two-sum/devyejin.py

@@ -1,15 +1,12 @@
-class Solution(object):
-    def twoSum(self, nums, target):
+from typing import List
 
-        nums_tuple = sorted(list(enumerate(nums)), key=lambda x: x[1])
-        left, right = 0, len(nums) - 1
 
-        while left < right:
-            temp_sum = nums_tuple[left][1] + nums_tuple[right][1]
-            if temp_sum == target:
-                return [nums_tuple[left][0], nums_tuple[right][0]]
-            elif temp_sum < target:
-                left += 1
-            else:
-                right -= 1
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        seen = {}
+        for idx, num in enumerate(nums):
+            need = target - num
+            if need in seen:
+                return [idx, seen[need]]
+            seen[num] = idx