为什么我的重载运算符返回零

无论出于什么原因，当我试图从重载函数返回值时，它都返回零。前几天我刚开始使用重载，所以我对它很陌生，所以如果这是一个简单的错误，我很抱歉。

这很奇怪，因为当我cout函数中的值时，它正好显示了我想要看到的内容，然而当我返回它时，它仍然返回一个空值，即零。

功能如下：

double operator+=(double ls, Account& rs){
    //cout << ls << endl;
    //cout << rs._balance+ ls << endl;
    return ls+=rs._balance;

    //return rs._balance+=ls;
}

这是完整的.cpp文件，包括以下函数：

#define _CRT_SECURE_NO_WARNINGS
#include <cstring>
#include <iomanip>
#include "Account.h"
using namespace std;
namespace sict{
    Account::Account(){
        _name[0] = 0;
        _balance = 0;
    }
    Account::Account(double balance){
        _name[0] = 0;
        _balance = balance;
    }
    Account::Account(const char name[], double balance){
        strncpy(_name, name, 40);
        _name[40] = 0;
        _balance = balance;
    }
    void Account::display()const{
        for(int x = 0; x < 40; x++){
            if(_name[x] == '')
                x = 40;
            else
                cout << _name[x];
        }
    cout << ": $" << setprecision(2) << fixed << _balance;
    }
    Account Account::operator+(Account ls) {
        return ls._balance + _balance;
    }
    double operator+=(double ls, Account& rs){
        //cout << ls << endl;
        //cout << rs._balance+ ls << endl;
        return ls+=rs._balance;

        //return rs._balance+=ls;
    }
    Account Account::operator+=(Account& ls){
        return  _balance+=ls._balance;
    }
    Account::Account(const char name[]){
        strncpy(_name, name, 40);
    }
    char* Account::getName(){
        return _name;
    }
    double Account::getBal(){
        return _balance;
    }
    std::ostream& operator<<(std::ostream& ls, Account& rs){
        rs.display();
        return ls;
    }
    Account& Account::operator=(Account& ls){
        if( !strcmp(ls._name,"") &&ls._balance > 0)
        {
            strcpy(_name, "Saving");
        }
        _balance = ls._balance;
        //strcpy(_name, ls._name);
        return *this;
    }
    char* Account::operator=(char* ls){
        strcpy(_name, ls);
        return _name;
    }

}

这是头文件：

#ifndef SICT_ACCOUNT_H__
#define SICT_ACCOUNT_H__
#include <iostream>
#include <cstring>
#include <iomanip>
namespace sict{
    class Account{
        char _name[41];
        double _balance;
    public:
        Account();
        Account::Account(double balance);
        Account::Account(const char name[], double balance);
        Account::Account(const char name[]);
        Account& operator=(Account& ls);
        Account operator+=(Account& ls);
        char* operator=(char* ls);
        void display()const;
        double getBal();
        char* getName();
        friend double operator+=(double ls, Account& rs);
        Account operator+(Account ls);
    };
    std::ostream& operator<<(std::ostream& ls, Account& rs);
};
#endif

主要内容如下：

#include <iostream>
#include <string>
#include "Account.h"
using namespace sict;
using namespace std;
int main()
{
  Account A;
  Account B("Saving", 10000.99);
  Account C("Checking", 100.99);
  double value = 0;
  cout << A << endl << B << endl << C << endl << "--------" << endl;
  A = B + C;
  A = "Joint";
  cout << A << endl << B << endl << C << endl << "--------" << endl;
  A = B += C;
  cout << A << endl << B << endl << C << endl << "--------" << endl;
  value += A;
  value += B;
  value += C;
  cout << "Total balance: " << value << endl;
  return 0;
}