187. 重复的DNA序列 所有 DNA 都由一系列缩写为 A,C,G 和 T 的核苷酸组成,例如:"ACGAATTCCG".在研究 DNA 时,识别 DNA 中的重复序列有时会对研究非常有帮助. 编写一个函数来查找 DNA 分子中所有出现超过一次的 10 个字母长的序列(子串). 示例: 输入:s = "AAAAACCCCCAAAAACCCCCCAAAAAGGGTTT" 输出:["AAAAACCCCC", "CCCCCAAAAA&qu…
Special binary strings are binary strings with the following two properties: The number of 0's is equal to the number of 1's. Every prefix of the binary string has at least as many 1's as 0's. Given a special string S, a move consists of choosing two…
Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascending order. Example 1…
Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation. For example: Given "aacecaaa", return "aaacecaaa&qu…
Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horizontally or vertically neighboring. The same le…
