Unique Binary Search Trees II99没看会神级解法Morris算法73通过或位运算简化代码,但未实现最简便的方法常数时间
Medium1453123FavoriteShareGivenanintegern,generateallstructurallyuniqueBST's(binarysearchtrees)thatstorevalues1...n.Example:Input:3Output:[ [1,null,3,2], [3,2,null,1], [3,1,null,null,2], [2,1,3], [1,n