在linux下编译简单的C++程序(第一次）

在linux中使用c++编译一个简单程序时出错。共有3个文件：Employee.h , Employee.cpp, and Salary.cpp (main)。我在Salary.cpp <iostream>, <fstream>, <string>, <stdio.h>, <stdlib.h>中包含了几个系统头。我使用的唯一原因是用于itoa()函数。我无法将它编译并读取到某个地方，而"有时是先决条件
我得到的错误是："Salary.cpp:195:47:error:itoa未在此范围中声明"

现在，我已经在全局范围中包含了头，而itoa（）只在我包含的文件中使用，所以我不知道为什么会发生这种情况，除了它没有包含正确的系统头之外。我需要在命令行中指定所有的系统头吗？我不太清楚发生了什么事。

编辑：以下是一些源代码。。。我只详细介绍了保持简短所需的内容。错误发生在底部附近的addEmployee（）函数中。。。我不知道该怎么写行号。它就在创建一个新的Employee（）之后

#include "Employee.h"
#include <iostream>
#include <fstream>
#include <string>
#include <cstdio>
#include <cstdlib>

void findEmployees(Employee*[], const short);
void addEmployee(Employee*[], short&);
unsigned short parseDataFile(Employee* [], short);
bool insertEmployee(Employee*[], short, Employee*);
int main(int argc, char** argv)
{
    //100 employees max, too lazy to create dynamic container
    Employee* employeeList[100];
    //Parse data file, return the length of the list made
    short listLen = parseDataFile(employeeList, 100);
    //Employee database is built, run query engine
    std::cout << "*************************************************n";
    std::cout << "This program lets you search for salaries of employees or input new employee information.n";
    std::cout << "*************************************************nnn";
    char choice = { 0 };
    while (true)
    {
        std::cout << "Please choose an option: n";
        std::cout << "(1) Search for employee salaries.n";
        std::cout << "(2) Input new employee datan";
        std::cout << "(3) Exitnn";
        std::cin >> choice;
        switch (choice)
        {
        case '1':
            findEmployees(employeeList, listLen - 1);
            break;
        case '2':
            addEmployee(employeeList, listLen);
            break;
        case '3':
            exit(0);
            break;
        }
    }
    return 0;
}
unsigned short parseDataFile(Employee* empList[], short len)
{
    //Do stuff
}
void findEmployees(Employee* empList[], const short len)
{
    //Do stuff
}
void addEmployee(Employee* empList[], short& len)
{
    char first[32] = "";
    char last[32] = "";
    char salary[32] = "";
    char id[32] = "";
    bool loop = true;
    while (loop)
    {
        std::cout << "Input Last Name:  ";
        std::cin.clear();
        std::cin.sync();
        std::cin.getline(last, 31);
        std::cout << std::endl << std::endl;
        std::cout << "Input First Name:  ";
        //Get user name
        std::cin.clear();
        std::cin.sync();
        std::cin.getline(first, 31);
        std::cout << std::endl << std::endl;
        std::cout << "Input Salary:  $";
        //Get user name
        std::cin.clear();
        std::cin.sync();
        std::cin.getline(salary, 31);
        std::cout << std::endl << std::endl;
        Employee* employee = new Employee();
        employee->setID( itoa((int)len, id, 10) ); //Set id
        employee->setFirstName(first); //Set first name
        employee->setLastName(last); //Set last name
        employee->setSalary(salary); //Set salary
        //Inserts new employee at the end of the list, no real reason to sort the list for this assignment
        //I guess I could have used std::vector to make it easy
        empList[len] = employee;
        ++len; //Increment length of the list
        char yesNo = { 0 };
        std::cout << "Would you like to enter another employee?  (Y, N):  ";
        std::cin >> yesNo;
        std::cout << std::endl << std::endl;
        switch (yesNo)
        {
            case 'Y':
            case 'y':
                //do nothing
            break;
            case 'N':
            case 'n':
                loop = false;
            break;
        }        
    }
}