C相同数组的不同数据[重复]

这个问题在这里已有答案：

• C++ correct way to return pointer to array from function 7个答案

• C++: Reference to “out of scope” object 3个答案

我在C编程 . 构造函数中的数组值与get_data的成员函数不同 .

for(int k = 0; k < 8; k++)
        {
            cout << "The invoice for " << *(categories_invo + k)  << endl;
        }

和，

for(int k = 0; k < 8; k++)
        {
            cout << "The invoice for get_data function is " << *(categories_invo + k)  << endl;
        }

get_data函数中的数组值似乎是随机的 . 有人能找出错误吗？谢谢 .

#include <iostream>
#include <cstdlib>
using namespace std;

class Invoice
{
    friend class FuncInvoice;

private:
    int uni_num;
    string month;
    float amount;
    string *name_categories;
    float *categories_invo;
    Invoice *next;

public:
    Invoice(int uni_num, float amount, string month, string *n_c, float *cate)
    {
        this->uni_num = uni_num;
        this->amount = amount;
        this->month = month;
        name_categories = n_c;
        categories_invo = cate;
        next = 0;
        for(int k = 0; k < 8; k++)
        {
            cout << "The invoice for " << *(categories_invo + k)  << endl;
        }

    }
    Invoice *get_next()
    {
        return next;
    }
    void get_data()
    {
        cout << "The invoices for " << month << endl;
        cout << "The unique invoice number is: " << uni_num << endl;

        for(int k = 0; k < 8; k++)
        {
            cout << "The invoice for get_data function is " << *(categories_invo + k)  << endl;
        }
    }
};

class FuncInvoice
{
private:
    Invoice *head;

public:
    FuncInvoice()
    {
        head = 0;
    }
    Invoice *begin()
    {
        return head;
    }
    void insert(Invoice *n)
    {
        n->next = head;
        head = n;
    }
};

FuncInvoice lists;

void add();
void display();

int main()
{
    add();
    display();
    system("pause");
    return 0;
}

void add()
{
    int i = 0;
    int uni_num;
    string mon_name[12] = {"Jan", "Feb", "March", "April", "May", "June", "July", "Aug", "Sept", "Oct", "Nov", "Dec"};
    string name_categories[8] = {"fuel", "food", "clothing", "holidays", "gifts", "gym", "books", "movies"};
    float categories[8];
    string command;
    do
    {
        cout << "The invoices are recorded for: " << mon_name[i] << endl;
        cout << "The unique number is: " << endl;
        cin >> uni_num;
        float amount = 0;
        for(int j = 0; j < 8; j++)
        {
            cout << "The invoice for " << name_categories[j] << " is:" << endl;
            cin >> categories[j];
            amount = amount + categories[j];
        }
        Invoice *object = new Invoice(uni_num, amount, mon_name[i], name_categories, categories);
        lists.insert(object);
        i++;
        cout << "Do you want to finish input? Please type \"yes\" or \"no\":" << endl;
        cin >> command;
    } while(i < 12 && (command != "yes"));

}

void display()
{
    Invoice *object;
    for(object = lists.begin(); object != 0; object = object->get_next())
    {
        object->get_data();
    }
}

结果显示：

The invoices are recorded for: Jan
The unique number is:
1
The invoice for fuel is:
1
The invoice for food is:
2
The invoice for clothing is:
3
The invoice for holidays is:
4
The invoice for gifts is:
5
The invoice for gym is:
6
The invoice for books is:
7
The invoice for movies is:
8
The invoice for 1
The invoice for 2
The invoice for 3
The invoice for 4
The invoice for 5
The invoice for 6
The invoice for 7
The invoice for 8
Do you want to finish input? Please type "yes" or "no":
yes
The invoices for Jan
The unique invoice number is: 1
The invoice for get_data function is 1.4013e-045
The invoice for get_data function is 1.4013e-045
The invoice for get_data function is 1.54143e-044
The invoice for get_data function is 3.69695e+033
The invoice for get_data function is 1.01927e-038
The invoice for get_data function is 1.01926e-038
The invoice for get_data function is 1.01927e-038
The invoice for get_data function is 6.4661e-039