Map接口实现Collection接口,是集合三大接口之一. Map接口在声明:public interface Map<K,V>;将键映射到值的对象,一个映射不能包含重复的键,每个键最多只能映射到一个值,如果一个键映射到多个值,其前面映射的值将会被后面映射的值所覆盖,其映射关系的实现类主要是HasgMap和TreeMap类,HashMap的映射实现不保存顺序,TreeMap的映射实现,可明确保证其顺序. 1.HashMap HashMap声明: public class HashMap<…
1.Object-Oriented ['əbdʒekt'ɔ:rɪəntɪd] 面向对象 adj 2.inheritance [ɪnˈherɪtəns] 继承;遗传;遗产 n inherit [ɪnˈherɪt] 继承 v 3.encapsulation 包装,封装,包裹 n encapsulate [ɪnˈkæpsjuleɪt] 封装;概述 v 4.polymorphism [ˌpɒlɪ'mɔ:fɪzəm] 多型现象,多态性;多机组合形式;多形性 n 5.constant [ˈkɒ…
E. Tourists time limit per test: 2 seconds memory limit per test: 256 megabytes input: standard input output :standard output There are n cities in Cyberland, numbered from 1 to n, connected by m bidirectional roads. The j-th road connects city aj an…
1004. Counting Leaves (30) A family hierarchy is usually presented by a pedigree tree. Your job is to count those family members who have no child. Input Each input file contains one test case. Each case starts with a line containing 0 < N < 100,…
Iterator definitions An iterator is any object that, pointing to some element in a range of elements (such as an array or a container), has the ability to iterate through the elements of that range using a set of operators (with at least the incremen…
集合 使用set或multiset之前,必须加入头文件<set> Set.multiset都是集合类,差别在与set中不允许有重复元素,multiset中允许有重复元素. sets和multiset内部以平衡二叉树实现 1. 常用函数 1) 构造函数和析构函数 set c:创建空集合,不包含任何元素 set c(op):以op为排序准则,产生一个空的set set c1(c2):复制c2中的元素到c1中 set c(const value_type *first, const…
Zhejiang University has 6 campuses and a lot of gates. From each gate we can collect the in/out times and the plate numbers of the cars crossing the gate. Now with all the information available, you are supposed to tell, at any specific time point, t…
对象数组举例: 学生类: package itcast01; /** * Created by gao on 15-12-9. */ public class Student { private String name; private int age; public Student() { } public Student(String name, int age) { this.name = name; this.age = age; } public String getName() {…
