Given a 2D binary matrix filled with 0’s and 1’s, find the largest rectangle containing only 1’s and return its area.
Example:
Input:
[
["1","0","1","0","0"],
["1","0","1","1","1"],
["1","1","1","1","1"],
["1","0","0","1","0"]
]
Output: 6
在给出的矩阵中，1表示元素，0表示空，找出最大矩形的面积。
Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).
Example:
Input: S = "ADOBECODEBANC", T = "ABC" Output: "BANC"Note:
- If there is no such window in S that covers all characters in T, return the empty string “”.
- If there is such window, you are guaranteed that there will always be only one unique minimum window in S.
给出两个字符串S和T，在S中找到一个最短的子串，它包含T中所有的字符。
Determine if a 9x9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:
- Each row must contain the digits
1-9without repetition.- Each column must contain the digits
1-9without repetition.- Each of the 9
3x3sub-boxes of the grid must contain the digits1-9without repetition.
A partially filled sudoku which is valid.
The Sudoku board could be partially filled, where empty cells are filled with the character
'.'.
验证数独
Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target.
Note: The solution set must not contain duplicate quadruplets.
For example, given array S = [1, 0, -1, 0, -2, 2], and target = 0. A solution set is: [ [-1, 0, 0, 1], [-2, -1, 1, 2], [-2, 0, 0, 2] ]
在给定数组中找出“和为 target 的四个数”的所有解。
Write a program to solve a Sudoku puzzle by filling the empty cells. Empty cells are indicated by the character ‘.’. You may assume that there will be only one unique solution.
Longest Substring Without Repeating Characters
Given a string, find the length of the longest substring without repeating characters.
Given “abcabcbb”, the answer is “abc”, which the length is 3.
Given “bbbbb”, the answer is “b”, with the length of 1.
Given “pwwkew”, the answer is “wke”, with the length of 3. Note that the answer must be a substring, “pwke” is a subsequence and not a substring.
在给定字符串中找出无重复字符的最长子串。
Given an array of integers, return indices of the two numbers such that they add up to a specific target.
You may assume that each input would have exactly one solution, and you may not use the same element twice.
Example:
Given nums = [2, 7, 11, 15], target = 9,
Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].
假定只有唯一解的情况下在数组中找出和为target的两个数
