# LeetCode Basic Calculator II

LeetCode Basic Calculator II Implement a basic calculator to evaluate a simple expression string. The expression string contains only non-negative integers, +, -, *, / operators and empty spaces . The integer division should truncate toward zero. You... Read More

# LeetCode Basic Calculator

LeetCode Basic Calculator Implement a basic calculator to evaluate a simple expression string. The expression string may contain open ( and closing parentheses ), the plus + or minus sign -, non-negative integers and empty spaces . You may assume that... Read More

# LeetCode Unique Substrings in Wraparound String

LeetCode Unique Substrings in Wraparound String Consider the string s to be the infinite wraparound string of "abcdefghijklmnopqrstuvwxyz", so s will look like this: "...zabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcd....". Now we have... Read More

# LeetCode Word Break

LeetCode Word Break Given a non-empty string s and a dictionary wordDict containing a list of non-empty words, determine if s can be segmented into a space-separated sequence of one or more dictionary words. You may assume the dictionary does not... Read More

# LeetCode Add Bold Tag in String

LeetCode Add Bold Tag in String Given a string s and a list of strings dict, you need to add a closed pair of bold tag <b> and </b> to wrap the substrings in s that exist in dict. If two such substrings overlap, you need to wrap them... Read More

# LeetCode Design Compressed String Iterator

LeetCode Design Compressed String Iterator Design and implement a data structure for a compressed string iterator. It should support the following operations: next and hasNext. The given compressed string will be in the form of each letter followed by... Read More

# LeetCode Palindrome Partitioning

LeetCode Palindrome Partitioning Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s. For example, given s = "aab", Return , ... Read More

# LeetCode Minimum Index Sum of Two Lists

LeetCode Minimum Index Sum of Two Lists Suppose Andy and Doris want to choose a restaurant for dinner, and they both have a list of favorite restaurants represented by strings. You need to help them find out their common interest with the least list... Read More

# LeetCode Tag Validator

LeetCode Tag Validator Given a string representing a code snippet, you need to implement a tag validator to parse the code and return whether it is valid. A code snippet is valid if all the following rules hold: The code must be wrapped in a valid... Read More

# LeetCode Find Duplicate File in System

LeetCode Find Duplicate File in System Given a list of directory info including directory path, and all the files with contents in this directory, you need to find out all the groups of duplicate files in the file system in terms of their paths. A... Read More