STL之map学习实例

```
#include<iostream>
#include<algorithm>
#include<vector>
#include<map>
#include<cstring>
#include<cstdlib>
#include<ctime>
using namespace std;

#define SALE_DEPATMENT 1//销售部门
#define DEVELOP_DEPATMENT 2//研发部门
#define FINACIAL_DEPATMENT 3//财务部门

/*multimap案例
公司今天招聘了5个员工，5名员工进入公司之后，需要指派员工在那个部门工作
人员信息有：姓名 年龄 电话 工资等组成
通过multimap 进行信息的插入 保存 显示
分部门显示员工信息 显示全部员工信息*/

class Worker{
public:
    string mName;
    string mTele;
    int mAge;
    int mSalary;
};

void Creat_Worker(vector<Worker>& vWorker){
    string seedName="ABCDE";
    for( int i=0; i<5; i++ ){
        Worker worker;
        worker.mName="员工";
        worker.mName+=seedName[i];

        worker.mAge=rand()%10+20;
        worker.mTele="010-8888888";
        worker.mSalary=rand()%10000+10000;
        //保存员工信息
        vWorker.push_back(worker);

    }
}

//员工分组
void WorkerByGroup(vector<Worker>& vWorker,multimap<int,Worker>& WorkerGroup){
    //把员工随机分配到不同的部门
    srand(time(NULL));
    for(vector<Worker>::iterator it=vWorker.begin(); it!=vWorker.end(); it++ ){
        int departID=rand()%3+1;
        switch(departID){
        case SALE_DEPATMENT:
            WorkerGroup.insert(make_pair(SALE_DEPATMENT,*it));
            break;
        case DEVELOP_DEPATMENT:
            WorkerGroup.insert(make_pair(DEVELOP_DEPATMENT,*it));
            break;
        case FINACIAL_DEPATMENT:
            WorkerGroup.insert(make_pair(FINACIAL_DEPATMENT,*it));
            break;
        default:
            break;
        }
    }

}

void ShowGroupWorkers(multimap<int,Worker>& WorkerGroup,int departID){
    multimap<int,Worker>::iterator it=WorkerGroup.find(departID);
    int DepartCount=WorkerGroup.count(departID);
    int num=0;
    for( ;num<DepartCount&&it!=WorkerGroup.end(); it++,num++ ){
        cout<<"姓名："<<it->second.mName<<" 年龄："<<it->second.mAge<<" 电话："
        <<it->second.mTele<<" 工资："<<it->second.mSalary<<endl;
    }
}

//打印每一部门的员工信息
void PrintWorkerByGroup(multimap<int,Worker>& WorkerGroup){
    //打印销售部员工信息
    cout<<"销售部门"<<endl;
    ShowGroupWorkers(WorkerGroup,SALE_DEPATMENT);
    //打印研发部员工信息
    cout<<"研发部门"<<endl;
    ShowGroupWorkers(WorkerGroup,DEVELOP_DEPATMENT);
    //打印财务部员工信息
    cout<<"财务部门"<<endl;
    ShowGroupWorkers(WorkerGroup,FINACIAL_DEPATMENT);

}


int main(){
    //存放新员工的信息
    vector<Worker> vWorker;
    //multimap保存分组信息
    multimap<int,Worker> WorkerGroup;
    //创建员工
    Creat_Worker(vWorker);
    //员工分组
    WorkerByGroup(vWorker,WorkerGroup);
    //打印每一部门的员工信息
    PrintWorkerByGroup(WorkerGroup);

    return 0;
}

```