Question

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

class Book
{
    int isbn;
    string price;
public:
    void setDetails()
    {
        cout << "ISBN ?" ;
        cin >> isbn;
        cout << "Price ?";
        cin >> price;
    }

    void getDetails()
    {
        cout << "ISBN: " << isbn;
        cout << "Price: " << price;
    }
};

int main()
{
    int a;
    vector<Book> books;
    cout << "How many books to insert ?";
    cin >> a;
    for(int i = 0; i < a; i++)
        {
            books[i].setDetails();
        }
    for(int j = 0; j < a; j++)
        {
            books[j].getDetails();
        }


}

当我运行程序时，在我输入isbn值后的那一刻，程序崩溃了。我找不到出了什么问题。我的主要功能有问题吗？

Answer 1

你没有在向量中推送任何元素。您需要使用push_back或resize

推送它们

int a;
vector<Book> books;
cout << "How many books to insert ?";
cin >> a;
books.resize( a ); // added by jpo38
for(int i = 0; i < a; i++)
{
    books[i].setDetails();
}
for(int j = 0; j < a; j++)
{
    books[j].getDetails();
}

Answer 2

你的矢量是空的。尝试添加以下行：

vector<Book> books;
cout << "How many books to insert ?";
cin >> a;
// Add this line:
books.resize(a);

Answer 3

尝试像这样更改它，我尝试了它，

 int a;
    cout << "How many books to insert ?";
    cin >> a;

    vector<Book> books(a);

即先获取大小并构造具有该大小的向量，这样就不会遇到分段错误

程序崩溃了。找不到什么错

3 个答案: