Two Sum Problem

twoSum.py

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+# Time Complexity : O(n)
+# Space Complexity : O(n)
+# Did this code successfully run on Leetcode : Yes
+# Any problem you faced while coding this : No
+# Approach: Use a hashmap to store (number : index) for numbers seen so far.
+# For each nums[i], check if its complement (target - nums[i]) already exists in the hashmap.
+# If yes, return the stored index and current index, otherwise store nums[i] with its index.
+
+
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        h_map = {}
+        for i in range(len(nums)):
+            if target - nums[i] in h_map:
+                return [h_map[target - nums[i]], i]
+            h_map[nums[i]] = i
+
+        return [-1, -1]
+