一个简单的计算机系统登录统计模拟程序

本程序主要是温习一下vector容器的用法：

#include<iostream>
#include<string>
#include<fstream>
#include<vector>

#include<cassert>
using namespace std;

template <typename Info>

class LoginLog
{
    public:
        void build(std::string filename);
        int search(Info item) const;
        void display(std::ostream &out) const;
    private:
        vector<Info> myUserLog;
};

template <typename Info>
void LoginLog<Info>::build(string filename)
{
    ifstream fin(filename.data());
    assert(fin.is_open());
    Info userInfo;
    for(;;)
    {
        fin>>userInfo;
        if(fin.eof()) break;
        int pos=search(userInfo);
        if(pos==myUserLog.size())
            myUserLog.push_back(userInfo);
    }
}
template <typename Info>
int LoginLog<Info>::search(Info item) const
{
    int i;
    for(i=0;i<myUserLog.size();i++)
        if(item==myUserLog[i])
            break;
        return i;
}

template <typename Info>
inline void LoginLog<Info>::display(ostream &out) const
{
    for(int i=0;i<myUserLog.size()-1;i++)
        out<<myUserLog[i]<<endl;
}
int main(void)
{
    string userInfoFile;
    char buffer[9];
    ofstream outFile;
    outFile.open("Log.txt");//在当前工作目录下创建一个文档
    if(!outFile.is_open())
    {
        cout<<"Could not opened!";
        return -1;
    }
    cout<<"now input the content of the log ,(input ok to end ) "<<endl;
    for(;;)//往文件中写内容
    {

        cin.getline(buffer,9);
        outFile<<buffer;
        outFile<<"\n";
        if(strcmp(buffer,"ok")==0)
            break;
    }
    outFile.close();
    cout<<"Enter name of login-info file:";
    getline(cin,userInfoFile);

    LoginLog<string> userIdLog;

    userIdLog.build(userInfoFile);

    cout<<"\n List of distinct user-ids who logged in :\n";

    userIdLog.display(cout);
}