✨ [217] Thought process 200 but hash map is still faster than 2 pointer

Author: enkr1

217/my_solution.js

@@ -4,34 +4,57 @@
  */
 const containsDuplicate = (nums) => {
   // nums = [1, 2, 3, 1]
-  let isDuplicated = false, l = 0, r = nums.length - 1;
+  let map = {}, l = 0, r = nums.length - 1;
+  // const map = new Map(nums.map((value, index) => [value, index]));
+  // console.log(map)
 
-  // for
-  // think about other edge cases ...
-  // for (let i = 0; i < nums.length; i++) {
-  //   if (l == r) {
-  //
-  //   }
-
-  while (r >= l) {
-    if (l === r) {
-      l++;
-      r = nums.length - 1;
+  for (let i = 0; i < nums.length; i++) {
+    if (undefined === map[nums[i]]) {
+      map[nums[i]] = i;
       continue;
     }
 
-    if (nums[l] === nums[r]) {
-      isDuplicated = true;
-      break;
-    } else {
-      r--;
-    }
+    return true;
   }
+  console.log("??")
+  console.log(map)
 
-  return isDuplicated;
+  return false;
 }
 
-containsDuplicate([1, 2, 3, 1])
+// containsDuplicate([1, 2, 3, 1])
 containsDuplicate([1, 2, 3, 4])
-containsDuplicate([1, 1, 1, 3, 3, 4, 3, 2, 4, 2])
+// containsDuplicate([1, 1, 1, 3, 3, 4, 3, 2, 4, 2])
 // containsDuplicate()
+
+// 2 pointer solution
+// const containsDuplicate = (nums) => {
+//   // nums = [1, 2, 3, 1]
+//   let isDuplicated = false, l = 0, r = nums.length - 1;
+//   const map = new Map(nums.map((value, index) => [value, index]));
+//   console.log(map)
+//
+//   // for
+//   // think about other edge cases ...
+//   // for (let i = 0; i < nums.length; i++) {
+//   //   if (l == r) {
+//   //
+//   //   }
+//
+//   while (r >= l) {
+//     if (l === r) {
+//       l++;
+//       r = nums.length - 1;
+//       continue;
+//     }
+//
+//     if (nums[l] === nums[r]) {
+//       isDuplicated = true;
+//       break;
+//     } else {
+//       r--;
+//     }
+//   }
+//
+//   return isDuplicated;
+// }

217/solution.js

@@ -3,21 +3,36 @@
  * @return {boolean}
  */
 const containsDuplicate = (nums) => {
-  let l = 0, r = nums.length - 1;
+  let map = {};
 
-  while (r >= l) {
-    if (l === r) {
-      l++;
-      r = nums.length - 1;
+  for (let i = 0; i < nums.length; i++) {
+    if (undefined === map[nums[i]]) {
+      map[nums[i]] = i;
       continue;
     }
 
-    if (nums[l] === nums[r]) {
-      return true
-    } else {
-      r--;
-    }
+    return true;
   }
 
   return false;
 }
+
+// const containsDuplicate = (nums) => {
+//   let l = 0, r = nums.length - 1;
+//
+//   while (r >= l) {
+//     if (l === r) {
+//       l++;
+//       r = nums.length - 1;
+//       continue;
+//     }
+//
+//     if (nums[l] === nums[r]) {
+//       return true
+//     } else {
+//       r--;
+//     }
+//   }
+//
+//   return false;
+// }

README.md

@@ -49,4 +49,5 @@ Quick create in bash
 ```ssh
 chapter=217 && mkdir ./$chapter && touch ./$chapter/my_solution.js && touch ./$chapter/solution.js
 # And TOC above
+alias x="node ./$chapter/my_solution"
 ```