2015 年 12月 29 日随笔档案 - neverlandly

2015年12月29日

Leetcode: Range Sum Query 2D - Immutable

摘要：阅读全文

posted @ 2015-12-29 09:25 neverlandly 阅读(320) 评论(0) 推荐(0)

摘要： Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive. Example: Given nums = [-2, 0, 3, -5, 2, -1] sumR 阅读全文

posted @ 2015-12-29 08:56 neverlandly 阅读(227) 评论(0) 推荐(0)

Leetcode: Smallest Rectangle Enclosing Black Pixels

摘要： An image is represented by a binary matrix with 0 as a white pixel and 1 as a black pixel. The black pixels are connected, i.e., there is only one bla 阅读全文

posted @ 2015-12-29 08:28 neverlandly 阅读(935) 评论(0) 推荐(0)

Leetcode: Longest Increasing Subsequence

摘要：讲解一：用一个数组来存 the smallest tail of all increasing subsequences with length i+1 in tails[i]. For example, say we have nums = [4,5,6,3], then all the ava 阅读全文

posted @ 2015-12-29 06:07 neverlandly 阅读(424) 评论(0) 推荐(0)

Leetcode: Bulls and Cows

摘要： Be careful, when calculate B, you should exclude A's cases 阅读全文

posted @ 2015-12-29 04:52 neverlandly 阅读(335) 评论(0) 推荐(0)

Leetcode: Serialize and Deserialize Binary Tree

摘要： Referring this post: https://leetcode.com/problems/serialize-and-deserialize-binary-tree/discuss/74253/Easy-to-understand-Java-Solution But instead us 阅读全文

posted @ 2015-12-29 03:16 neverlandly 阅读(376) 评论(0) 推荐(0)

Leetcode: Binary Tree Longest Consecutive Sequence

摘要：递归法复杂度时间O(n) 空间O(h) 思路因为要找最长的连续路径，我们在遍历树的时候需要两个信息，一是目前连起来的路径（curLen）有多长（以当前节点为终点），二是目前路径的上一个节点的值(preVal)。每一次递归，先检查当前节点是否比上一节点大1, 是，curLen++, 否curL 阅读全文

posted @ 2015-12-29 01:11 neverlandly 阅读(361) 评论(0) 推荐(0)