Added tasks 416-1143

src/main/ts/g0001_0100/s0001_two_sum/readme.md

@@ -43,19 +43,16 @@ You can return the answer in any order.
 ## Solution
 
 ```typescript
-interface ITemp {
-    [key: number]: number
-}
-
 function twoSum(nums: number[], target: number): number[] {
-    const temp: ITemp = {}
+    const indexMap: Map<number, number> = new Map()
     for (let i = 0; i < nums.length; i++) {
-        const tag = target - nums[i]
-        if (temp[tag] >= 0) {
-            return [temp[tag], i]
+        const requiredNum: number = target - nums[i]
+        if (indexMap.has(requiredNum)) {
+            return [indexMap.get(requiredNum)!, i]
         }
-        temp[nums[i]] = i
+        indexMap.set(nums[i], i)
     }
+    return [-1, -1]
 }
 
 export { twoSum }

src/main/ts/g0001_0100/s0002_add_two_numbers/readme.md

@@ -54,29 +54,29 @@ import { ListNode } from '../../com_github_leetcode/listnode'
  * }
  */
 function addTwoNumbers(l1: ListNode | null, l2: ListNode | null): ListNode | null {
-    const result = new ListNode(null)
-    let next = result
-    let carryNum = 0
-    let currSum = 0
-    let num1 = 0
-    let num2 = 0
-
-    while (l1 !== null || l2 !== null) {
-        // @ts-ignore
-        num1 = l1 !== null ? l1.val : 0
-        // @ts-ignore
-        num2 = l2 !== null ? l2.val : 0
-        currSum = (num1 + num2 + carryNum) % 10
-        carryNum = Math.floor((num1 + num2 + carryNum) / 10)
-        next.next = new ListNode(currSum)
-        next = next.next
-        l1 = l1 !== null ? l1.next : null
-        l2 = l2 !== null ? l2.next : null
+    const dummyHead: ListNode = new ListNode(0)
+    let p: ListNode | null = l1
+    let q: ListNode | null = l2
+    let curr: ListNode | null = dummyHead
+    let carry: number = 0
+    while (p !== null || q !== null) {
+        const x: number = p !== null ? p.val : 0
+        const y: number = q !== null ? q.val : 0
+        const sum: number = carry + x + y
+        carry = Math.floor(sum / 10)
+        curr.next = new ListNode(sum % 10)
+        curr = curr.next
+        if (p !== null) {
+            p = p.next
+        }
+        if (q !== null) {
+            q = q.next
+        }
     }
-    if (carryNum) {
-        next.next = new ListNode(carryNum)
+    if (carry > 0) {
+        curr.next = new ListNode(carry)
     }
-    return result.next
+    return dummyHead.next
 }
 
 export { addTwoNumbers }

src/main/ts/g0001_0100/s0003_longest_substring_without_repeating_characters/readme.md

@@ -44,21 +44,27 @@ Notice that the answer must be a substring, "pwke" is a subsequence and not a su
 
 ```typescript
 function lengthOfLongestSubstring(s: string): number {
-    const hash: { [key: string]: number } = {}
-    let maxLength = 0
-    let length = 0
-    let start = 0
+    const lastIndices: number[] = new Array(256).fill(-1)
+    let maxLen: number = 0
+    let curLen: number = 0
+    let start: number = 0
     for (let i = 0; i < s.length; i++) {
-        const char = s[i]
-        if (hash[char] !== undefined && hash[char] >= start) {
-            start = hash[char] + 1
-            length = i - start
+        const cur: string = s.charAt(i)
+        const charCode: number = cur.charCodeAt(0)
+        if (lastIndices[charCode] < start) {
+            lastIndices[charCode] = i
+            curLen++
+        } else {
+            const lastIndex: number = lastIndices[charCode]
+            start = lastIndex + 1
+            curLen = i - start + 1
+            lastIndices[charCode] = i
+        }
+        if (curLen > maxLen) {
+            maxLen = curLen
         }
-        length++
-        hash[char] = i
-        maxLength = Math.max(maxLength, length)
     }
-    return maxLength
+    return maxLen
 }
 
 export { lengthOfLongestSubstring }

src/main/ts/g0001_0100/s0005_longest_palindromic_substring/readme.md

@@ -30,30 +30,33 @@ Given a string `s`, return _the longest_ _palindromic_ _substring_ in `s`.
 
 ```typescript
 function longestPalindrome(s: string): string {
-    let max = 0
-    let res = ''
+    const newStr: string[] = new Array(s.length * 2 + 1)
+    newStr[0] = '#'
     for (let i = 0; i < s.length; i++) {
-        for (let j = i + 1; j <= s.length; j++) {
-            if (s.slice(i, j).length > max && isPalindrome(s.slice(i, j))) {
-                max = s.slice(i, j).length
-                res = s.slice(i, j)
-            }
-        }
+        newStr[2 * i + 1] = s.charAt(i)
+        newStr[2 * i + 2] = '#'
     }
-    return res
-}
-
-const isPalindrome = (s: string): boolean => {
-    let i = 0
-    let j = s.length - 1
-    while (i < j) {
-        if (s[i] !== s[j]) {
-            return false
+    const dp: number[] = new Array(newStr.length)
+    let friendCenter: number = 0
+    let friendRadius: number = 0
+    let lpsCenter: number = 0
+    let lpsRadius: number = 0
+    for (let i = 0; i < newStr.length; i++) {
+        dp[i] =
+            friendCenter + friendRadius > i ? Math.min(dp[2 * friendCenter - i], friendCenter + friendRadius - i) : 1
+        while (i + dp[i] < newStr.length && i - dp[i] >= 0 && newStr[i + dp[i]] === newStr[i - dp[i]]) {
+            dp[i]++
+        }
+        if (friendCenter + friendRadius < i + dp[i]) {
+            friendCenter = i
+            friendRadius = dp[i]
+        }
+        if (lpsRadius < dp[i]) {
+            lpsCenter = i
+            lpsRadius = dp[i]
         }
-        i++
-        j--
     }
-    return true
+    return s.substring((lpsCenter - lpsRadius + 1) / 2, (lpsCenter + lpsRadius - 1) / 2)
 }
 
 export { longestPalindrome }

src/main/ts/g0401_0500/s0416_partition_equal_subset_sum/readme.md

@@ -0,0 +1,54 @@
+[![](https://img.shields.io/github/stars/LeetCode-in-TypeScript/LeetCode-in-TypeScript?label=Stars&style=flat-square)](https://github.com/LeetCode-in-TypeScript/LeetCode-in-TypeScript)
+[![](https://img.shields.io/github/forks/LeetCode-in-TypeScript/LeetCode-in-TypeScript?label=Fork%20me%20on%20GitHub%20&style=flat-square)](https://github.com/LeetCode-in-TypeScript/LeetCode-in-TypeScript/fork)
+
+## 416\. Partition Equal Subset Sum
+
+Medium
+
+Given a **non-empty** array `nums` containing **only positive integers**, find if the array can be partitioned into two subsets such that the sum of elements in both subsets is equal.
+
+**Example 1:**
+
+**Input:** nums = [1,5,11,5]
+
+**Output:** true
+
+**Explanation:** The array can be partitioned as [1, 5, 5] and [11]. 
+
+**Example 2:**
+
+**Input:** nums = [1,2,3,5]
+
+**Output:** false
+
+**Explanation:** The array cannot be partitioned into equal sum subsets. 
+
+**Constraints:**
+
+*   `1 <= nums.length <= 200`
+*   `1 <= nums[i] <= 100`
+
+## Solution
+
+```typescript
+function canPartition(nums: number[]): boolean {
+    let sums: number = 0
+    for (const num of nums) {
+        sums += num
+    }
+    if (sums % 2 === 1) {
+        return false
+    }
+    sums /= 2
+    const dp: boolean[] = new Array(sums + 1).fill(false)
+    dp[0] = true
+    for (const num of nums) {
+        for (let sum = sums; sum >= num; sum--) {
+            dp[sum] = dp[sum] || dp[sum - num]
+        }
+    }
+    return dp[sums]
+}
+
+export { canPartition }
+```

src/main/ts/g0401_0500/s0437_path_sum_iii/readme.md

@@ -0,0 +1,63 @@
+[![](https://img.shields.io/github/stars/LeetCode-in-TypeScript/LeetCode-in-TypeScript?label=Stars&style=flat-square)](https://github.com/LeetCode-in-TypeScript/LeetCode-in-TypeScript)
+[![](https://img.shields.io/github/forks/LeetCode-in-TypeScript/LeetCode-in-TypeScript?label=Fork%20me%20on%20GitHub%20&style=flat-square)](https://github.com/LeetCode-in-TypeScript/LeetCode-in-TypeScript/fork)
+
+## 437\. Path Sum III
+
+Medium
+
+Given the `root` of a binary tree and an integer `targetSum`, return _the number of paths where the sum of the values along the path equals_ `targetSum`.
+
+The path does not need to start or end at the root or a leaf, but it must go downwards (i.e., traveling only from parent nodes to child nodes).
+
+**Example 1:**
+
+![](https://assets.leetcode.com/uploads/2021/04/09/pathsum3-1-tree.jpg)
+
+**Input:** root = [10,5,-3,3,2,null,11,3,-2,null,1], targetSum = 8
+
+**Output:** 3
+
+**Explanation:** The paths that sum to 8 are shown. 
+
+**Example 2:**
+
+**Input:** root = [5,4,8,11,null,13,4,7,2,null,null,5,1], targetSum = 22
+
+**Output:** 3 
+
+**Constraints:**
+
+*   The number of nodes in the tree is in the range `[0, 1000]`.
+*   <code>-10<sup>9</sup> <= Node.val <= 10<sup>9</sup></code>
+*   `-1000 <= targetSum <= 1000`
+
+## Solution
+
+```typescript
+function pathSum(root: TreeNode | null, targetSum: number): number {
+    let count = 0
+    let map = new Map<number, number>()
+
+    function dfs(node: TreeNode | null, currentSum: number): void {
+        if (!node) return
+
+        currentSum += node.val
+        if (currentSum === targetSum) count++
+
+        count += map.get(currentSum - targetSum) ?? 0
+
+        map.set(currentSum, map.get(currentSum) + 1 || 1)
+        dfs(node?.left, currentSum)
+        dfs(node?.right, currentSum)
+
+        //remove from hashmap
+        map.set(currentSum, map.get(currentSum) - 1)
+        if (map.get(currentSum) === 0) map.delete(currentSum)
+    }
+
+    dfs(root, 0)
+    return count
+}
+
+export { pathSum }
+```

src/main/ts/g0401_0500/s0438_find_all_anagrams_in_a_string/readme.md

@@ -0,0 +1,79 @@
+[![](https://img.shields.io/github/stars/LeetCode-in-TypeScript/LeetCode-in-TypeScript?label=Stars&style=flat-square)](https://github.com/LeetCode-in-TypeScript/LeetCode-in-TypeScript)
+[![](https://img.shields.io/github/forks/LeetCode-in-TypeScript/LeetCode-in-TypeScript?label=Fork%20me%20on%20GitHub%20&style=flat-square)](https://github.com/LeetCode-in-TypeScript/LeetCode-in-TypeScript/fork)
+
+## 438\. Find All Anagrams in a String
+
+Medium
+
+Given two strings `s` and `p`, return _an array of all the start indices of_ `p`_'s anagrams in_ `s`. You may return the answer in **any order**.
+
+An **Anagram** is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.
+
+**Example 1:**
+
+**Input:** s = "cbaebabacd", p = "abc"
+
+**Output:** [0,6]
+
+**Explanation:**
+
+    The substring with start index = 0 is "cba", which is an anagram of "abc".
+    The substring with start index = 6 is "bac", which is an anagram of "abc". 
+
+**Example 2:**
+
+**Input:** s = "abab", p = "ab"
+
+**Output:** [0,1,2]
+
+**Explanation:**
+
+    The substring with start index = 0 is "ab", which is an anagram of "ab".
+    The substring with start index = 1 is "ba", which is an anagram of "ab".
+    The substring with start index = 2 is "ab", which is an anagram of "ab". 
+
+**Constraints:**
+
+*   <code>1 <= s.length, p.length <= 3 * 10<sup>4</sup></code>
+*   `s` and `p` consist of lowercase English letters.
+
+## Solution
+
+```typescript
+function findAnagrams(s: string, p: string): number[] {
+    const map: number[] = new Array(26).fill(0)
+    for (let i = 0; i < p.length; ++i) {
+        map[p.charCodeAt(i) - 'a'.charCodeAt(0)]++
+    }
+    const res: number[] = []
+    let i: number = 0
+    let j: number = 0
+
+    while (i < s.length) {
+        const idx: number = s.charCodeAt(i) - 'a'.charCodeAt(0)
+        // Add the new character
+        map[idx]--
+        // If the length is greater than window's length, pop the left character in the window
+        if (i >= p.length) {
+            map[s.charCodeAt(j++) - 'a'.charCodeAt(0)]++
+        }
+        let finish: boolean = true
+
+        for (let k = 0; k < 26; k++) {
+            // If it is not an anagram of string p
+            if (map[k] !== 0) {
+                finish = false
+                break
+            }
+        }
+
+        if (i >= p.length - 1 && finish) {
+            res.push(j)
+        }
+        i++
+    }
+    return res
+}
+
+export { findAnagrams }
+```