Implement a queue with two stacks so that each queue operations takes a constant amortized number of stack operations. 题目要求用栈实现队列的所有操作。 1packageweek2;23importjava.util.Stack;45/**6* Queue with two stacks. Implement a queue with two stacks so that each queue7* operations takes...
Execution: java QueueWithTwoStacks < input.txt 4 * Dependencies: StdIn.java StdOut.java 5 * Data files: http://algs4.cs.princeton.edu/13stacks/tobe.txt 6 * 7 * A generic queue, implemented using two stacks. 8 * 9 * % java QueueWithTwoStacks < tobe.txt 10 * to be or not ...
with self.assertRaises(Exception): queue.dequeue() def test_error_when_dequeue_from_empty_queue(self): queue = QueueTwoStacks() queue.enqueue(1) queue.enqueue(2) actual = queue.dequeue() expected = 1 self.assertEqual(actual, expected) actual = queue.dequeue() expected = 2 self.assertEqual...
Implement queue with two stack 用两个堆实现队列 在上国外某教授的algorithm课,课后有一个小quiz,问题如下 Implement a queue with two stacks so that each queue operations takes a constant amortized number of stack operations. 用两个堆实现一个队列,这个队列每次操作的消耗应该是堆操作的分期常量。 我们...
push (int data):Insertion at top int pop():Deletion from top Implementing Queue using stack A queue can be implanted using stack also. We need two stacks for implementation. The basic idea behind the implementation is to implement the queue operations (enqueue, dequeue) with stack operations ...
http://www.lintcode.com/en/problem/implement-queue-by-two-stacks/ 【题目解析】 用两个Stack来实现一个Queue,可以考虑到push()时,几乎与Queue中的offer()一样,都是加在末尾,区别是当Stack pop()时,取出的是最近加入(newest)的元素,而Queue用poll()则是将最老(oldest)的元素取出。使用2个Stack,可以将...
The idea is to reduce the problem to the problem of stacks, which was already solved by us. So we only need to learn how to simulate a queue using two stacks. We make two stacks,s1ands2. Of course these stack will be of the modified form, so that we can find the minimum in ...
Have you ever had to make a queue out of two stacks or make a stack out of two queues on a whiteboard? You might remember that by creating a queue using two stacks you inherently are choosing to make enqueue or dequeue costly. You also might be more familiar with the simple linked lis...
用两个栈来实现一个队列,完成队列的Push和Pop操作。 队列中的元素为int类型。 classSolution{public:voidpush(intnode){}intpop(){}private:stack<int>stack1;stack<int>stack2;}; 问题 1.栈和队列分别是怎么样的数据结构,有什么样的特点? 2.如何使用两个栈实现一个队列 ...
题目地址:https://leetcode.com/problems/implement-trie-prefix-tree/description/ 题目描述 Implement a trie with insert, search, and startsWith methods. Example: Note: 题目大意 实现字典树。字典树: 上图是一棵Trie树,表示一个保存了8个键的trie结... ...