When you begin to practice algorithms and data structures with LeetCode problems.

Remember to build your confidence and find the fun of algorihtms in your first step.

You should start with easy problems.

This is a list of categories with classic and easy problems for you.

Array

Remove Element

Remove Duplicates from Sorted Array

Remove Duplicates from Sorted Array II

Find the Celebrity

Rotate Array

String

Implement strStr()

Longest Common Prefix

Length of Last Word

First Unique Character in a String

Ransom Note

Reverse String

Reverse Words in a String

Tree

Binary Tree Preorder Traversal

Binary Tree Inorder Traversal

Binary Tree Postorder Traversal

Binary Tree Level Order Traversal

Same Tree

Sum Root to Leaf Numbers

LinkedList

Reverse Linked List

Linked List Cycle

Add Two Numbers

Intersection of Two Linked Lists

DFS & BFS

Number of Islands

Walls and Gates

Surrounded Regions

Backtracking

Subsets

Permutations

Combination Sum

Other references

How To Learn Data Structures And Algorithms is a roadmap for newbie.

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