摘要：
Given a string S and a string T, count the number of distinct subsequences of S which equals T. A subsequence of a string is a new string which is for 阅读全文
摘要：
Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. Example 1: Example 2: Approach #1: DP. [C++] Analysis: status: match[s1L 阅读全文
摘要：
Given n, how many structurally unique BST's (binary search trees) that store values 1 ... n? Example: Approach #1: DP. [C++] Analysis: status: nums[n] 阅读全文