test: add more test cases

Author: wislertt

leetcode/two_sum/playground.ipynb

@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 1,
    "id": "imports",
    "metadata": {},
    "outputs": [],
@@ -13,7 +13,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 2,
    "id": "setup",
    "metadata": {},
    "outputs": [],
@@ -26,21 +26,43 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 3,
    "id": "run",
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[0, 1]"
+      ]
+     },
+     "execution_count": 3,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "result = run_two_sum(Solution, nums, target)\n",
     "result"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 4,
    "id": "assert",
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "True"
+      ]
+     },
+     "execution_count": 4,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "assert_two_sum(result, expected)"
    ]
@@ -60,7 +82,8 @@
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
-   "nbconvert_exporter": "python3",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
    "version": "3.13.7"
   }
  },

leetcode/two_sum/solution.py

@@ -1,7 +1,12 @@
 class Solution:
 
-    # Time: O(?)
-    # Space: O(?)
+    # Time: O(n)
+    # Space: O(n)
     def two_sum(self, nums: list[int], target: int) -> list[int]:
-        # TODO: Implement two_sum
+        seen: dict[int, int] = {}
+        for i, num in enumerate(nums):
+            complement = target - num
+            if complement in seen:
+                return [seen[complement], i]
+            seen[num] = i
         return []