呀，天亮了
Mar 23, 2020 07:12:13 AM
https://leetcode.com/problems/edit-distance/
Given two words word1 and word2, find the minimum number of operations required to convert word1 to word2.
You have the following 3 operations permitted on a word:
Example 1:
Input: word1 = "horse", word2 = "ros" Output: 3 Explanation: horse -> rorse (replace 'h' with 'r') rorse -> rose (remove 'r') rose -> ros (remove 'e')
Mar 23, 2020 04:32:17 AM
https://leetcode.com/problems/longest-common-subsequence/
Given two strings text1 and text2, return the length of their longest common subsequence.
A subsequence of a string is a new string generated from the original string with some characters(can be none) deleted without changing the relative order of the remaining characters. (eg, "ace" is a subsequence of "abcde" while "aec" is not). A common subsequence of two strings is a subsequence that is common to both strings.
If there is no common subsequence, return 0.
Example 1:
Input: text1 = "abcde", text2 = "ace" Output: 3 Explanation: The longest common subsequence is "ace" and its length is 3.
Mar 23, 2020 04:23:14 AM
https://leetcode.com/problems/longest-increasing-subsequence/
Given an unsorted array of integers, find the length of longest increasing subsequence.
Example:
Input:[10,9,2,5,3,7,101,18]Output: 4 Explanation: The longest increasing subsequence is[2,3,7,101], therefore the length is4.
Mar 19, 2020 12:10:32 PM
https://leetcode.com/problems/unique-binary-search-trees/
Given n, how many structurally unique BST's (binary search trees) that store values 1 ... n?
Example:
Input: 3
Output: 5
Explanation:
Given n = 3, there are a total of 5 unique BST's:
1 3 3 2 1
\ / / / \ \
3 2 1 1 3 2
/ / \ \
2 1 2 3
Mar 19, 2020 07:49:54 AM
https://leetcode.com/problems/ugly-number-ii/
Write a program to find the n-th ugly number.
Ugly numbers are positive numbers whose prime factors only include 2, 3, 5.
Example:
Input: n = 10 Output: 12 Explanation:1, 2, 3, 4, 5, 6, 8, 9, 10, 12is the sequence of the first10ugly numbers.
Mar 15, 2020 08:04:22 AM
https://leetcode.com/problems/partition-equal-subset-sum/
Given a non-empty array containing only positive integers, find if the array can be partitioned into two subsets such that the sum of elements in both subsets is equal.
Note:
Example 1:
Input: [1, 5, 11, 5] Output: true Explanation: The array can be partitioned as [1, 5, 5] and [11].
Mar 04, 2020 03:35:57 AM
https://leetcode.com/problems/unique-paths-ii/
A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).
The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).
Now consider if some obstacles are added to the grids. How many unique paths would there be?
An obstacle and empty space is marked as 1 and 0 respectively in the grid.
Note: m and n will be at most 100.
Example 1:
Input: [ [0,0,0], [0,1,0], [0,0,0] ] Output: 2 Explanation: There is one obstacle in the middle of the 3x3 grid above. There are two ways to reach the bottom-right corner: 1. Right -> Right -> Down -> Down 2. Down -> Down -> Right -> Right
Mar 04, 2020 03:09:55 AM
https://leetcode.com/problems/minimum-path-sum/
Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.
Note: You can only move either down or right at any point in time.
Example:
Input: [ [1,3,1], [1,5,1], [4,2,1] ] Output: 7 Explanation: Because the path 1→3→1→1→1 minimizes the sum.
