每日一题--设计一个呼叫中心系统（Google面试推荐书Cracking the Coding Interview）

题目：
假设有个呼叫中心，有接线员、经理、主管三种角色。如果接线员无法处理呼叫，就上传给经理；如果仍无法处理，则上传给主管。请用代码描述这一过程。

分析：
典型的职责链设计模式的题目，今天第一次练习，该题目可以大概设计成两个类：

1. 打电话的客户类（初步设计为包含客户名字和客户等级）；
2. 服务人员（一个抽象基类+接线员、经理、主管三个继承类，初步设计为包含接电话服务，后续准备加上接电话者工号，是否需要排序等待这些功能）

！！！设计有待完善（关于接线员、经理、主管人数的设计等），先贴上今日版完成的代码。
代码：

#include<iostream>
#include<string>
using namespace std;

class Caller {
	public:
		Caller(string name, int rank) {
			this->mCallername = name;
			this->mRank = rank;
		};
	
		int getRank(){
			return mRank;
		};
	
		string getName() {
			return mCallername;
		};
		
		~Caller(){};
	
	private:
		string mCallername;
		int mRank;
};

class Woker {
	public:
		Woker() {};
		virtual void handelcall(Caller* caller) = 0;
		virtual ~Woker(){};		
};

class Director: public Woker {
	public:
		Director(string name) {this->mDirectorname = name;};
		virtual void handelcall(Caller* caller){
			if(caller->getRank() == 2) {
				cout << "Director" << this->mDirectorname << " is handling " << caller->getName() << "'s call." << endl;
			}
			else {
				cout << "Sorry we can't answer " << caller->getName() << "'s question." << endl;
			}
		};
		virtual ~Director(){};
	
	private:
		string mDirectorname;
};

class Manager: public Woker {
	public:
		Manager(string name) {this->mManagername = name;};
		virtual void handelcall(Caller* caller){
			if(caller->getRank() == 1) {
				cout << "Manager " << this->mManagername << " is handling " << caller->getName() << "'s call." << endl;
			}
			else {
				Woker* woker = new Director("主管1");
				woker ->handelcall(caller);
				delete woker ;
			}
		};
		virtual ~Manager(){};
		
	private:
		string mManagername;
};

class Respondent: public Woker {
	public:
		Respondent(string name) {this->mRespondentname = name;};
		virtual void handelcall(Caller* caller){
			if(caller->getRank() == 0) {
				cout << "Respondent " << this->mRespondentname << " is handling " << caller->getName() << "'s call" << endl;
			}
			else {
				Woker* woker = new Manager("经理1");
				woker->handelcall(caller);
				delete woker;
			}
		};
		virtual ~Respondent() {};
	private:
		string mRespondentname;
};

int main() {
	Woker* woker = new Respondent("接线员1");
	
	enum rank{
		junior,
		middle,
		senior,
		other
	}; 
	
	Caller* caller1 = new Caller("张三", middle);
	Caller* caller2 = new Caller("李四", junior);
	Caller* caller3 = new Caller("王五", senior);
	Caller* caller4 = new Caller("赵六", other);
	
	woker->handelcall(caller1);
	woker->handelcall(caller2);
	woker->handelcall(caller3);
	woker->handelcall(caller4);
	
	delete woker; 
	delete caller1;
	delete caller2;
	delete caller3;
	delete caller4;
	return 0;
}

结果展示：