标签归档：leetcode

题目描述：

LeetCode 420. Strong Password Checker

A password is considered strong if below conditions are all met:

1. It has at least 6 characters and at most 20 characters.
2. It must contain at least one lowercase letter, at least one uppercase ...

题目描述：

LeetCode 433. Minimum Genetic Mutation

A gene string can be represented by an 8-character long string, with choices from "A","C","G","T". 

Suppose we need to investigate about a mutation (mutation from "start" to "end"), where ONE mutation is defined as ...

题目描述：

LeetCode 432. All O`one Data Structure

Implement a data structure supporting the following operations:

1. Inc(Key) - Inserts a new key with value 1. Or increments an existing key by 1. Key is guaranteed to be a non-empty string.
2. Dec(Key) ...

LeetCode Weekly Contest 9是LeetCode举办的第八场正式周赛，共4道题目，比赛时长2.5小时。

比赛链接：https://leetcode.com/contest/leetcode-weekly-contest-9/

题解列表：

LeetCode 422. Valid Word Square

LeetCode 423. Reconstruct Original Digits from English

LeetCode 424. Longest Repeating Character Replacement

LeetCode 425. Word Squares

题目描述：

LeetCode 425. Word Squares

Given a set of words (without duplicates), find all word squares you can build from them.

A sequence of words forms a valid word square if the k^th row and column read the ...