Create 1-Two-Sum.py

Author: neetcode-gh

1-Two-Sum.py

@@ -0,0 +1,9 @@
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        prevMap = {} # val -> index
+        
+        for i, n in enumerate(nums):
+            diff = target - n
+            if diff in prevMap:
+                return [prevMap[diff], i]
+            prevMap[n] = i