我该如何读回我在C ++中的文本文件中编写的相同变量？

Question

这里是一个程序，要求我将员工的数据保存在一个文本文件中，然后从该文件中读取数据，并找出ID为13的员工的薪水，我不知道如何读回我之前存储在文件中的相同变量，会有所帮助。

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
const int size=3;
struct employees
{
    int id;
    string name;
    int salary;
    int age;
}emp[size];
int main() 
{
    ofstream file;
    file.open("employee.txt",ios::out);
    cout<<"\t------Enter data in the file------\n";
    int count=1;
    for(int i=0;i<size;i++)
    {
        cout<<"\tEnter info of employee "<<count<<endl;
        cout<<"Enter the age:\n";
        cin>>emp[i].age;
        file<<"Age of the employee:\n";
        file<<emp[i].age<<endl;
        cout<<"Enter the name:\n";
        cin>>emp[i].name;
        file<<"Name of the employee:\n";
        file<<emp[i].name<<endl;
        cout<<"Enter the id:\n";
        cin>>emp[i].id;
        file<<"ID of the employee:\n";
        file<<"ID= "<<emp[i].id<<endl;
        cout<<"Enter the Salary:\n";
        cin>>emp[i].salary;
        file<<" Salary of the employee:\n";
        file<<emp[i].salary<<endl; 
        count++;
    }
    file.close();
    ifstream file2;
    file2.open("employee.txt",ios::in);

    //Here goes the reading part

    file2.close();
    return 0;
}