Add two-sum solution

Author: Jeehay28

two-sum/Jeehay28.js

@@ -0,0 +1,49 @@
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number[]}
+ */
+
+
+// Time Complexity : O(n)
+// Space Complexity : O(n)
+
+var twoSum = function (nums, target) {
+
+    let map = new Map();
+
+    for (let i = 0; i < nums.length; i++) {
+
+        const temp = target - nums[i];
+
+        if (map.has(temp)) {
+            return [i, map.get(temp)]
+        }
+
+        map.set(nums[i], i);
+    }
+
+    return [];
+}
+
+
+// Time Complexity: O(n^2)
+// Space Complexity: O(1)
+// This solution is straightforward but inefficient for large arrays. For better performance, consider the hashmap approach.
+
+// var twoSum = function (nums, target) {
+
+//     for (let i = 0; i < nums.length; i++) {
+
+//         const loc = nums.indexOf((target - nums[i]), i + 1);
+
+//         if (loc >= 0) {
+//             return [i, loc]
+//         } else {
+//             continue;
+//         }
+
+//     }
+
+// };
+