solve: Week 01 Two Sum

Author: eunice-hong

two-sum/eunice-hong.ts

@@ -0,0 +1,24 @@
+/**
+ * Finds two numbers in the array that add up to the target value.
+ * Uses a hash map to store previously seen numbers for O(n) time complexity.
+ *
+ * @param nums - An array of integers.
+ * @param target - The target sum.
+ * @returns A tuple containing the indices of the two numbers.
+ *
+ * Time Complexity: O(n)
+ * Space Complexity: O(n)
+ */
+function twoSum(nums: number[], target: number): number[] {
+  const map = new Map<number, number>();
+
+  for (let i = 0; i < nums.length; i++) {
+      const complement = target - nums[i];
+      if (map.has(complement)) {
+          return [map.get(complement)!, i];
+      }
+      map.set(nums[i], i);
+  }
+
+  throw new Error("No solution found");
+}