leetcode 解题思路

Given a singly linked list, return a random node's value from the linked list. Each node must have thesame probabilityof being chosen.Follow up:What if the linked list is extremely large and its length is unknown to you? Could you solve this efficient..

Given an array of integers with possible duplicates, randomly output the index of a given target number. You can assume that the given target number must exist in the array.Note:The array size c

感悟就是：坚持，才能从good到great。精益求精就是要不断打磨产品。Princeton的课就是好，一个作业可以牵扯到很多算法。复习了shuffle算法和Resevoir Sampling算法，还有linkedin，array implement deque，iterator的用法，确实不错的课程，经典就是经典！刷题不在乎刷题数目多少，而在于刷背后知识点的深度和广度。加油！我觉得我刷完A...