mofei

原题链接：Patching Array - LeetCode题目Given a sorted integer array nums and an integer n, add/patch elements to the array such that any number in the range [1, n] inclusive can be formed by the sum of some elements in the array.Return the minimum number of pa

原题链接：Unique Binary Search Trees - LeetCode题目Given an integer n, return *the number of structurally unique **BST’*s (binary search trees) which has exactly n nodes of unique values from 1 to n.Example 1:Input: n = 3Output: 5Example 2:Input: n = 1Ou

动态规划动态规划与分治方法相似，都是通过组合子问题的解来求解原问题。动态规划是分治方法的特例，应用于子问题重叠的情况。在这种情况下，分治算法会反复求解这些重叠的子问题。而动态规划算法对每个子问题只求解一次，将其解保存下来，而无需每次都计算。动态规划的实现有两种形式：递推形式和递归形式。