实验5

Posted 2020-11-08 -alone

#include<iostream>
#include<cstdlib>
#include<ctime>
using namespace std;
class Dice{
    public:
        Dice(int n);
        int cast()
        {
        int number=rand()%sides+1;
        return number;  
        }
        private:
            int sides;
};
Dice::Dice(int n)
{
    sides=n;
}
int main()
{
    int x;
    float count=0;
    cin>>x;
    Dice a(40);
    for(int times=0;times<=500;times++)
    {
        srand(times);
        int s=a.cast();
        if(s==x)
        count++;
    }
    float c=count/500;
    cout<<c<<endl;
    return 0;
}

#include<string>
#include<vector>
using namespace std;
class Book{
    public:
        Book(string isbnA,string titleA,float priceA);
        void print();
    private:
        string isbn;
        string title;
        float price;    
};
Book::Book(string isbnA,string titleA,float priceA)
{
    isbn=isbnA;
    title=titleA;
    price=priceA;
}
void Book::print(){
    cout<<isbn<<"   "<<title<<"   "<<price<<endl;
}
int main()
{
    vector<Book>books;
    string isbn,title;
    float price;
    int i=0;
    while(cin>>isbn>>title>>price){
        Book book(isbn,title,price);
        i++;
        books.push_back(book);
    }
    for(int k=0;k<i;k++)
    {
        books[k].print();
    }
    return 0;
}

#include<string>
using namespace std;
int main()
{
    int a=9; 
    int *p=&a;
    cout<<"The value at p:"<<*p;
    return 0;
}

#include<iostream>
using namespace std;
int fn1(){
    int *p=new int (5);
    return *p;
}
int main()
{
    int a=fn1();
    cout<<"The value of a is:"<<a;
    return 0;
}

课本6—18的题目并不清楚哪里错误，new int(5) 不懂是什么意思 程序运行直接出现结果 不明白错误在哪里。

实验3 不会。