第二周课程的Elementray Sorts部分练习测验Interview Questions的第3题荷兰国旗问题很有意思.题目的原文描述如下: Dutch national flag. Given an array of n buckets, each containing a red, white, or blue pebble, sort them by color. The allowed operations are: swap(i,j): swap the pebble in buc…

题目原文: Given two integer arrays of size n , design a subquadratic algorithm to determine whether one is a permutation of the other. That is, do they contain exactly the same entries but, possibly, in a different order. 本质上就是求两个数组排序后是否相等,鉴于本节课学的是选择.插入.…

题目原文: Given two arrays a[] and b[], each containing n distinct 2D points in the plane, design a subquadratic algorithm to count the number of points that are contained both in array a[] and array b[]. 题目的目标就是计算重复point的个数,很简单,代码如下 import java.awt.Poin…

2-Color Dutch National Flag Problem 问题 a[0..n-1]中包含红元素或蓝元素;重新放置使得 红元素均在蓝元素之前. 循环不变式 每一次循环,a[0...k-1]是红色 实例代码 #include <iostream> #include <vector> using namespace std; class Solution { public: //将仅包含1,2组成的数组用循环不变式的方式将数组转换成2在前面,1在后面. void loop_…

题目原文: 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. package week2; import java.util.Stack; /** * Queue with two stacks. Implement a queue with two stacks so tha…

题目原文: Design an algorithm to perform an inorder traversal of a binary search tree using only a constant amount of extra space. public void traverse(BST<Key,Value> bst) { traverse(bst.root.left, bst.root); } private void traverse(Node current, Node p…

题目原文: Given a binary tree where each …

1. Java autoboxing and equals(). Consider two double values a and b and their corresponding Double value x and y. Find values such that (…

题目原文: Stack with max. Create a data structure that efficiently supports the stack operations (push and pop) and also a return-the-maximum operation. Assume the elements are reals numbers so that you can compare them. 分析: 该题目要求在实现正常stack的push和pop操作外,还…

题目原文: Given a set of n integers S = {0,1,…,N-1}and a sequence of requests of the following form: Remove x from S Find the successor of x: the smallest y in S such thaty>=x design a data type so that all operations(except construction) take logarithmi…