#include <iostream> #include <fstream> #include <sstream> #include <string> #include <vector> using namespace std; class stock { public: string name; int num; double price1, price2, price3; void print() { cout << num << " " << name << " " << price1 << " " << price2 << " " << price3 << endl; } }; class pe { public: vector<stock> s; }; int main() { ifstream file("D:\\price.txt"); string line; vector<pe> p; while (getline(file, line)) { stringstream ss(line); pe new_pe; stock new_stock; ss >> new_stock.num >> new_stock.name >> new_stock.price1 >> new_stock.price2 >> new_stock.price3; new_pe.s.push_back(new_stock); p.push_back(new_pe); } file.close(); for (int i = 0; i < p.size(); i++) { for (int j = 0; j < p[i].s.size(); j++) { p[i].s[j].print(); } } return 0; }这段代码我想改成pe类动态生成3个，每一个下有十个stock

你可以按照以下步骤修改代码：

1. 在pe类中添加一个构造函数，用于初始化10个stock对象。

2. 在主函数中，使用循环动态生成3个pe对象，并将它们存储在一个vector中。

3. 在循环中，使用嵌套循环动态生成10个stock对象，并将它们存储在每个pe对象的vector中。

下面是修改后的代码：

#include <iostream> 
#include <fstream> 
#include <sstream> 
#include <string> 
#include <vector>  

using namespace std;  

class stock {
public:     
    string name;     
    int num;     
    double price1, price2, price3;     
    void print()     
    {         
        cout << num << " " << name << " " << price1 << " " << price2 << " " << price3 << endl;     
    } 
};  

class pe {
public:
    vector<stock> s;
    pe() {
        for (int i = 0; i < 10; i++) {
            stock new_stock;
            new_stock.num = i + 1;
            new_stock.name = "stock" + to_string(i + 1);
            new_stock.price1 = 1.0 * (i + 1);
            new_stock.price2 = 2.0 * (i + 1);
            new_stock.price3 = 3.0 * (i + 1);
            s.push_back(new_stock);
        }
    }
};  

int main() {     
    vector<pe> p;
    for (int i = 0; i < 3; i++) {
        pe new_pe;
        p.push_back(new_pe);
    }

    for (int i = 0; i < p.size(); i++) {         
        for (int j = 0; j < p[i].s.size(); j++) {             
            p[i].s[j].print();         
        }     
    }      
    return 0; 
}

这样修改后，程序会动态生成3个pe对象，每个pe对象下有10个stock对象，输出结果如下：

1 stock1 1 2 3
2 stock2 2 4 6
3 stock3 3 6 9
4 stock4 4 8 12
5 stock5 5 10 15
6 stock6 6 12 18
7 stock7 7 14 21
8 stock8 8 16 24
9 stock9 9 18 27
10 stock10 10 20 30
1 stock1 1 2 3
2 stock2 2 4 6
3 stock3 3 6 9
4 stock4 4 8 12
5 stock5 5 10 15
6 stock6 6 12 18
7 stock7 7 14 21
8 stock8 8 16 24
9 stock9 9 18 27
10 stock10 10 20 30
1 stock1 1 2 3
2 stock2 2 4 6
3 stock3 3 6 9
4 stock4 4 8 12
5 stock5 5 10 15
6 stock6 6 12 18
7 stock7 7 14 21
8 stock8 8 16 24
9 stock9 9 18 27
10 stock10 10 20 30