Google

🧠 Arrays & Strings (Very High Frequency)

• Two Sum – LeetCode 1

• Best Time to Buy and Sell Stock – 121

• Product of Array Except Self – 238

• Longest Substring Without Repeating Characters – 3

• Minimum Window Substring – 76

• Container With Most Water – 11

• Merge Intervals – 56

🔗 Linked List

• Reverse Linked List – 206

• Merge Two Sorted Lists – 21

• Linked List Cycle – 141

• Intersection of Two Linked Lists – 160

🌳 Trees & Binary Search Trees

• Binary Tree Level Order Traversal – 102

• Validate Binary Search Tree – 98

• Lowest Common Ancestor of a Binary Tree – 236

• Diameter of Binary Tree – 543

• Serialize and Deserialize Binary Tree – 297

🔍 Binary Search

• Binary Search – 704

• Search in Rotated Sorted Array – 33

• Find First and Last Position of Element in Sorted Array – 34