归档 2016年8月

题目描述：

LeetCode 384. Shuffle an Array

Shuffle a set of numbers without duplicates.

Example:

// Init an array with set 1, 2, and 3.
int[] nums = {1,2,3};
Solution solution = new Solution(nums);

// Shuffle the array [1,2,3] and ...

题目描述：

LeetCode 383. Ransom Note

Given an arbitrary ransom note string and another string containing letters from all the magazines, write a function that will return true if the ransom note can be constructed from the magazines; otherwise, it will ...

题目描述：

LeetCode 382. Linked List Random Node

Given a singly linked list, return a random node's value from the linked list. Each node must have the same probability of being chosen.

Follow up:
What if the linked list is extremely ...

题目描述：

LeetCode 381. Insert Delete GetRandom O(1) - Duplicates allowed

Design a data structure that supports all following operations in average O(1) time.

Note: Duplicate elements are allowed.

1. insert(val): Inserts an item val to the collection.
2. remove(val ...

题目描述：

LeetCode 380. Insert Delete GetRandom O(1)

Design a data structure that supports all following operations in O(1) time.

1. insert(val): Inserts an item val to the set if not already present.
2. remove(val): Removes an item val ...