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145# LeetCode Problems Summary
Here are all of the problems that I have solved on the LeetCode platform:
| Problem Name | ID | Difficulty | Topics |
|--------------|----|------------|--------|
| [Two Sum](https://leetcode.com/problems/two-sum/) | 1 | Easy | Array, Hash Table |
| [Add Two Numbers](https://leetcode.com/problems/add-two-numbers/) | 2 | Medium | Linked List, Math, Recursion |
| [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/) | 3 | Medium | Hash Table, String, Sliding Window |
| [Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays/) | 4 | Hard | Array, Binary Search, Divide and Conquer |
| [Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/) | 5 | Medium | Two Pointers, String, Dynamic Programming |
| [Zigzag Conversion](https://leetcode.com/problems/zigzag-conversion/) | 6 | Medium | String |
| [Reverse Integer](https://leetcode.com/problems/reverse-integer/) | 7 | Medium | Math |
| [Palindrome Number](https://leetcode.com/problems/palindrome-number/) | 9 | Easy | Math |
| [Container With Most Water](https://leetcode.com/problems/container-with-most-water/) | 11 | Medium | Array, Two Pointers, Greedy |
| [Integer to Roman](https://leetcode.com/problems/integer-to-roman/) | 12 | Medium | Hash Table, Math, String |
| [Roman to Integer](https://leetcode.com/problems/roman-to-integer/) | 13 | Easy | Hash Table, Math, String |
| [Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/) | 14 | Easy | Array, String, Trie |
| [3Sum](https://leetcode.com/problems/3sum/) | 15 | Medium | Array, Two Pointers, Sorting |
| [Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/) | 17 | Medium | Hash Table, String, Backtracking |
| [Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/) | 19 | Medium | Linked List, Two Pointers |
| [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/) | 20 | Easy | String, Stack |
| [Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/) | 21 | Easy | Linked List, Recursion |
| [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/) | 22 | Medium | String, Dynamic Programming, Backtracking |
| [Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/) | 23 | Hard | Linked List, Divide and Conquer, Heap (Priority Queue), Merge Sort |
| [Swap Nodes in Pairs](https://leetcode.com/problems/swap-nodes-in-pairs/) | 24 | Medium | Linked List, Recursion |
| [Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/) | 26 | Easy | Array, Two Pointers |
| [Remove Element](https://leetcode.com/problems/remove-element/) | 27 | Easy | Array, Two Pointers |
| [Find the Index of the First Occurrence in a String](https://leetcode.com/problems/find-the-index-of-the-first-occurrence-in-a-string/) | 28 | Easy | Two Pointers, String, String Matching |
| [Divide Two Integers](https://leetcode.com/problems/divide-two-integers/) | 29 | Medium | Math, Bit Manipulation |
| [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/) | 33 | Medium | Array, Binary Search |
| [Find First and Last Position of Element in Sorted Array](https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/) | 34 | Medium | Array, Binary Search |
| [Search Insert Position](https://leetcode.com/problems/search-insert-position/) | 35 | Easy | Array, Binary Search |
| [Valid Sudoku](https://leetcode.com/problems/valid-sudoku/) | 36 | Medium | Array, Hash Table, Matrix |
| [Count and Say](https://leetcode.com/problems/count-and-say/) | 38 | Medium | String |
| [Jump Game II](https://leetcode.com/problems/jump-game-ii/) | 45 | Medium | Array, Dynamic Programming, Greedy |
| [Permutations](https://leetcode.com/problems/permutations/) | 46 | Medium | Array, Backtracking |
| [Rotate Image](https://leetcode.com/problems/rotate-image/) | 48 | Medium | Array, Math, Matrix |
| [Group Anagrams](https://leetcode.com/problems/group-anagrams/) | 49 | Medium | Array, Hash Table, String, Sorting |
| [Pow(x, n)](https://leetcode.com/problems/powx-n/) | 50 | Medium | Math, Recursion |
| [N-Queens II](https://leetcode.com/problems/n-queens-ii/) | 52 | Hard | Backtracking |
| [Spiral Matrix](https://leetcode.com/problems/spiral-matrix/) | 54 | Medium | Array, Matrix, Simulation |
| [Jump Game](https://leetcode.com/problems/jump-game/) | 55 | Medium | Array, Dynamic Programming, Greedy |
| [Merge Intervals](https://leetcode.com/problems/merge-intervals/) | 56 | Medium | Array, Sorting |
| [Insert Interval](https://leetcode.com/problems/insert-interval/) | 57 | Medium | Array |
| [Length of Last Word](https://leetcode.com/problems/length-of-last-word/) | 58 | Easy | String |
| [Rotate List](https://leetcode.com/problems/rotate-list/) | 61 | Medium | Linked List, Two Pointers |
| [Unique Paths](https://leetcode.com/problems/unique-paths/) | 62 | Medium | Math, Dynamic Programming, Combinatorics |
| [Unique Paths II](https://leetcode.com/problems/unique-paths-ii/) | 63 | Medium | Array, Dynamic Programming, Matrix |
| [Add Binary](https://leetcode.com/problems/add-binary/) | 67 | Easy | Math, String, Bit Manipulation, Simulation |
| [Sqrt(x)](https://leetcode.com/problems/sqrtx/) | 69 | Easy | Math, Binary Search |
| [Climbing Stairs](https://leetcode.com/problems/climbing-stairs/) | 70 | Easy | Math, Dynamic Programming, Memoization |
| [Simplify Path](https://leetcode.com/problems/simplify-path/) | 71 | Medium | String, Stack |
| [Set Matrix Zeroes](https://leetcode.com/problems/set-matrix-zeroes/) | 73 | Medium | Array, Hash Table, Matrix |
| [Sort Colors](https://leetcode.com/problems/sort-colors/) | 75 | Medium | Array, Two Pointers, Sorting |
| [Combinations](https://leetcode.com/problems/combinations/) | 77 | Medium | Backtracking |
| [Remove Duplicates from Sorted Array II](https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/) | 80 | Medium | Array, Two Pointers |
| [Search in Rotated Sorted Array II](https://leetcode.com/problems/search-in-rotated-sorted-array-ii/) | 81 | Medium | Array, Binary Search |
| [Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/) | 82 | Medium | Linked List, Two Pointers |
| [Partition List](https://leetcode.com/problems/partition-list/) | 86 | Medium | Linked List, Two Pointers |
| [Merge Sorted Array](https://leetcode.com/problems/merge-sorted-array/) | 88 | Easy | Array, Two Pointers, Sorting |
| [Reverse Linked List II](https://leetcode.com/problems/reverse-linked-list-ii/) | 92 | Medium | Linked List |
| [Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/) | 94 | Easy | Stack, Tree, Depth-First Search, Binary Tree |
| [Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) | 98 | Medium | Tree, Depth-First Search, Binary Search Tree, Binary Tree |
| [Same Tree](https://leetcode.com/problems/same-tree/) | 100 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Symmetric Tree](https://leetcode.com/problems/symmetric-tree/) | 101 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/) | 104 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/) | 105 | Medium | Array, Hash Table, Divide and Conquer, Tree, Binary Tree |
| [Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/) | 108 | Easy | Array, Divide and Conquer, Tree, Binary Search Tree, Binary Tree |
| [Balanced Binary Tree](https://leetcode.com/problems/balanced-binary-tree/) | 110 | Easy | Tree, Depth-First Search, Binary Tree |
| [Minimum Depth of Binary Tree](https://leetcode.com/problems/minimum-depth-of-binary-tree/) | 111 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Path Sum](https://leetcode.com/problems/path-sum/) | 112 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Flatten Binary Tree to Linked List](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/) | 114 | Medium | Linked List, Stack, Tree, Depth-First Search, Binary Tree |
| [Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/) | 121 | Easy | Array, Dynamic Programming |
| [Best Time to Buy and Sell Stock II](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/) | 122 | Medium | Array, Dynamic Programming, Greedy |
| [Valid Palindrome](https://leetcode.com/problems/valid-palindrome/) | 125 | Easy | Two Pointers, String |
| [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/) | 128 | Medium | Array, Hash Table, Union Find |
| [Gas Station](https://leetcode.com/problems/gas-station/) | 134 | Medium | Array, Greedy |
| [Single Number](https://leetcode.com/problems/single-number/) | 136 | Easy | Array, Bit Manipulation |
| [Single Number II](https://leetcode.com/problems/single-number-ii/) | 137 | Medium | Array, Bit Manipulation |
| [Copy List with Random Pointer](https://leetcode.com/problems/copy-list-with-random-pointer/) | 138 | Medium | Hash Table, Linked List |
| [Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/) | 141 | Easy | Hash Table, Linked List, Two Pointers |
| [Insertion Sort List](https://leetcode.com/problems/insertion-sort-list/) | 147 | Medium | Linked List, Sorting |
| [Sort List](https://leetcode.com/problems/sort-list/) | 148 | Medium | Linked List, Two Pointers, Divide and Conquer, Sorting, Merge Sort |
| [Reverse Words in a String](https://leetcode.com/problems/reverse-words-in-a-string/) | 151 | Medium | Two Pointers, String |
| [Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/) | 153 | Medium | Array, Binary Search |
| [Find Minimum in Rotated Sorted Array II](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/) | 154 | Hard | Array, Binary Search |
| [Min Stack](https://leetcode.com/problems/min-stack/) | 155 | Medium | Stack, Design |
| [Find Peak Element](https://leetcode.com/problems/find-peak-element/) | 162 | Medium | Array, Binary Search |
| [Two Sum II - Input Array Is Sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/) | 167 | Medium | Array, Two Pointers, Binary Search |
| [Majority Element](https://leetcode.com/problems/majority-element/) | 169 | Easy | Array, Hash Table, Divide and Conquer, Sorting, Counting |
| [Rotate Array](https://leetcode.com/problems/rotate-array/) | 189 | Medium | Array, Math, Two Pointers |
| [Binary Tree Right Side View](https://leetcode.com/problems/binary-tree-right-side-view/) | 199 | Medium | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Number of Islands](https://leetcode.com/problems/number-of-islands/) | 200 | Medium | Array, Depth-First Search, Breadth-First Search, Union Find, Matrix |
| [Happy Number](https://leetcode.com/problems/happy-number/) | 202 | Easy | Hash Table, Math, Two Pointers |
| [Remove Linked List Elements](https://leetcode.com/problems/remove-linked-list-elements/) | 203 | Easy | Linked List, Recursion |
| [Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/) | 205 | Easy | Hash Table, String |
| [Minimum Size Subarray Sum](https://leetcode.com/problems/minimum-size-subarray-sum/) | 209 | Medium | Array, Binary Search, Sliding Window, Prefix Sum |
| [Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/) | 215 | Medium | Array, Divide and Conquer, Sorting, Heap (Priority Queue), Quickselect |
| [Contains Duplicate II](https://leetcode.com/problems/contains-duplicate-ii/) | 219 | Easy | Array, Hash Table, Sliding Window |
| [Count Complete Tree Nodes](https://leetcode.com/problems/count-complete-tree-nodes/) | 222 | Easy | Binary Search, Bit Manipulation, Tree, Binary Tree |
| [Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/) | 226 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Basic Calculator II](https://leetcode.com/problems/basic-calculator-ii/) | 227 | Medium | Math, String, Stack |
| [Summary Ranges](https://leetcode.com/problems/summary-ranges/) | 228 | Easy | Array |
| [Kth Smallest Element in a BST](https://leetcode.com/problems/kth-smallest-element-in-a-bst/) | 230 | Medium | Tree, Depth-First Search, Binary Search Tree, Binary Tree |
| [Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/) | 234 | Easy | Linked List, Two Pointers, Stack, Recursion |
| [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/) | 238 | Medium | Array, Prefix Sum |
| [Valid Anagram](https://leetcode.com/problems/valid-anagram/) | 242 | Easy | Hash Table, String, Sorting |
| [Single Number III](https://leetcode.com/problems/single-number-iii/) | 260 | Medium | Array, Bit Manipulation |
| [H-Index](https://leetcode.com/problems/h-index/) | 274 | Medium | Array, Sorting, Counting Sort |
| [First Bad Version](https://leetcode.com/problems/first-bad-version/) | 278 | Easy | Binary Search, Interactive |
| [Move Zeroes](https://leetcode.com/problems/move-zeroes/) | 283 | Easy | Array, Two Pointers |
| [Word Pattern](https://leetcode.com/problems/word-pattern/) | 290 | Easy | Hash Table, String |
| [Counting Bits](https://leetcode.com/problems/counting-bits/) | 338 | Easy | Dynamic Programming, Bit Manipulation |
| [Power of Four](https://leetcode.com/problems/power-of-four/) | 342 | Easy | Math, Bit Manipulation, Recursion |
| [Reverse Vowels of a String](https://leetcode.com/problems/reverse-vowels-of-a-string/) | 345 | Easy | Two Pointers, String |
| [Insert Delete GetRandom O(1)](https://leetcode.com/problems/insert-delete-getrandom-o1/) | 380 | Medium | Array, Hash Table, Math, Design, Randomized |
| [Ransom Note](https://leetcode.com/problems/ransom-note/) | 383 | Easy | Hash Table, String, Counting |
| [Find the Difference](https://leetcode.com/problems/find-the-difference/) | 389 | Easy | Hash Table, String, Bit Manipulation, Sorting |
| [Is Subsequence](https://leetcode.com/problems/is-subsequence/) | 392 | Easy | Two Pointers, String, Dynamic Programming |
| [Sum of Left Leaves](https://leetcode.com/problems/sum-of-left-leaves/) | 404 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Fizz Buzz](https://leetcode.com/problems/fizz-buzz/) | 412 | Easy | Math, String, Simulation |
| [Find All Duplicates in an Array](https://leetcode.com/problems/find-all-duplicates-in-an-array/) | 442 | Medium | Array, Hash Table, Sorting |
| [Find All Numbers Disappeared in an Array](https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/) | 448 | Easy | Array, Hash Table |
| [Delete Node in a BST](https://leetcode.com/problems/delete-node-in-a-bst/) | 450 | Medium | Tree, Binary Search Tree, Binary Tree |
| [Minimum Number of Arrows to Burst Balloons](https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/) | 452 | Medium | Array, Greedy, Sorting |
| [Hamming Distance](https://leetcode.com/problems/hamming-distance/) | 461 | Easy | Bit Manipulation |
| [Total Hamming Distance](https://leetcode.com/problems/total-hamming-distance/) | 477 | Medium | Array, Math, Bit Manipulation |
| [Find Bottom Left Tree Value](https://leetcode.com/problems/find-bottom-left-tree-value/) | 513 | Medium | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Minimum Absolute Difference in BST](https://leetcode.com/problems/minimum-absolute-difference-in-bst/) | 530 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Search Tree, Binary Tree |
| [Diameter of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/) | 543 | Easy | Tree, Depth-First Search, Binary Tree |
| [Reverse Words in a String III](https://leetcode.com/problems/reverse-words-in-a-string-iii/) | 557 | Easy | Two Pointers, String |
| [Can Place Flowers](https://leetcode.com/problems/can-place-flowers/) | 605 | Easy | Array, Greedy |
| [Merge Two Binary Trees](https://leetcode.com/problems/merge-two-binary-trees/) | 617 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Average of Levels in Binary Tree](https://leetcode.com/problems/average-of-levels-in-binary-tree/) | 637 | Easy | Tree, Depth-First Search, Breadth-First Search, Binary Tree |
| [Two Sum IV - Input is a BST](https://leetcode.com/problems/two-sum-iv-input-is-a-bst/) | 653 | Easy | Hash Table, Two Pointers, Tree, Depth-First Search, Breadth-First Search, Binary Search Tree, Binary Tree |
| [Maximum Binary Tree](https://leetcode.com/problems/maximum-binary-tree/) | 654 | Medium | Array, Divide and Conquer, Stack, Tree, Monotonic Stack, Binary Tree |
| [Jewels and Stones](https://leetcode.com/problems/jewels-and-stones/) | 771 | Easy | Hash Table, String |
| [Greatest Common Divisor of Strings](https://leetcode.com/problems/greatest-common-divisor-of-strings/) | 1071 | Easy | Math, String |
| [Minimum Flips to Make a OR b Equal to c](https://leetcode.com/problems/minimum-flips-to-make-a-or-b-equal-to-c/) | 1318 | Medium | Bit Manipulation |
| [Linked List in Binary Tree](https://leetcode.com/problems/linked-list-in-binary-tree/) | 1367 | Medium | Linked List, Tree, Depth-First Search, Binary Tree |
| [Merge Strings Alternately](https://leetcode.com/problems/merge-strings-alternately/) | 1768 | Easy | Two Pointers, String |
| [Minimum Additions to Make Valid String](https://leetcode.com/problems/minimum-additions-to-make-valid-string/) | 2645 | Medium | String, Dynamic Programming, Stack, Greedy |
| [Delete Nodes From Linked List Present in Array](https://leetcode.com/problems/delete-nodes-from-linked-list-present-in-array/) | 3217 | Medium | Array, Hash Table, Linked List |