如何使用三個參數化構造函數的rand（）函數初始化對象數組？

Question

這是一個從數組中查找最大和最小Box的程序。 如何自動生成隨機數並將其存儲在數組中？

如何自動生成長度，寬度和高度並將其存儲在對象數組中？

#include <iostream>
#include <stdlib.h>

using namespace std;

 class Box{
private:
    double length;
    double height;
    double width;
    //parameterized constructor for the Box class to initialized length, height and width
    public:
    Box(double ilength,double iheight,double iwidth){
    length=ilength;
    height=iheight;
    width=iwidth;
    }

    //calculate the volume
    double getvolume(){
    return length*height*width;
    }
    //calculate the width
    double getarea(){
    return 2*width*length+2*length*height+2*height*width;
    }


};



int main()
{
//Generate the value of length, height and width of every box
double e=(rand()%6)+1;
double f=(rand()%6)+1;
double g=(rand()%6)+1;
double i=(rand()%7)+1;
double j=(rand()%8)+1;
double k=(rand()%9)+1;
double l=(rand()%10)+1;
double m=(rand()%11)+1;
double n=(rand()%12)+1;

cout<<e<<"this is e"<<endl;
cout<<f<<"this is f"<<endl;
cout<<g<<"this is g"<<endl;
cout<<i<<"this is i"<<endl;
cout<<j<<"this is j"<<endl;
cout<<k<<"this is k"<<endl;
cout<<l<<"this is l"<<endl;
cout<<m<<"this is m"<<endl;
cout<<n<<"this is n"<<endl;

Box b[3]={Box(e,f,g),Box(i,j,k),Box(l,m,n)};

double c,d,h,a;
c=b[1].getvolume();
d=b[1].getarea();
h=b[0].getvolume();
a=b[0].getarea();


cout << c <<endl;
cout<< d<<endl;
return 0;
}

這可行，但是還有其他更好的方法嗎？

Answer 1

如果所有盒子的模量值都可以相同，我將執行以下操作：

#include <algorithm>    
Box b[3]; 
std::generate(std::begin(b), std::end(b), []()mutable{return Box(rand()%6+1, rand()%7+1, rand()%8+1);});

您需要向Box類添加默認構造函數：

Box() = default;