Create twoSum.py

src/twoSum.py

@@ -0,0 +1,33 @@
+def twoSum(nums: list[int], target: int) -> list[int]:
+    """
+    Given an array of integers nums and an integer target, 
+    return indices of the two numbers that add up to target.
+
+    Args:
+        nums: List of integers
+        target: Target sum
+
+    Returns:
+        List containing indices of two numbers that sum to target
+
+    Example:
+        Input: nums = [2,7,11,15], target = 9
+        Output: [0,1]
+        Explanation: Because nums[0] + nums[1] == 9, we return [0, 1]
+    """
+    # Create hash map to store complement values
+    seen = {}
+
+    # Iterate through array once, O(n) time complexity
+    for i, num in enumerate(nums):
+        complement = target - num
+
+        # If we've seen the complement before, we found our pair
+        if complement in seen:
+            return [seen[complement], i]
+
+        # Store current number and its index
+        seen[num] = i
+
+    # No solution found
+    return []