我正在尝试编写一个程序
• 定义一个由五个圆形对象组成的数组，其中半径是使用随机类提供的随机数设置的，该随机类利用参数化的构造函数
• 定义第二个包含五个圆形对象的数组，其中半径是使用随机类提供的随机数设置的，该随机类使用 setRadius 方法
• 显示每个数组中每个圆的面积，使用getArea()
我需要帮助以使用 getArea() 方法显示每个数组中每个圆的面积的问题，我需要访问每个数组中具有五个圆的半径值的数组，然后计算出面积 3.14 * Radius * Radius . 然后将该区域显示到屏幕上。
同样在做了一些研究之后，我是否需要对我输入的 Circle 对象进行实例化Circle myCircle;。但是它带有一个错误说
1>main.obj : 错误 LNK2019: 函数 _main 中引用的未解析外部符号“public: __thiscall Circle::Circle(void)”(??0Circle@@QAE@XZ)
Circle.h 文件
#pragma once
#include <string>
class Circle
{
private:
float Radius;
public:
Circle(); // initialised radius to 0
Circle(float r); // accepts an argument and assign its value to the radius attribute
void setRadius(float r); // sets radius to a value provided by its radius parameter (r)
float getRadius(); // returns the radius of a circle
float getArea(); // calculates and returns the areas of its circle
};
随机.h 文件
#pragma once
#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;
class Random
{
public:
static void initialiseSeed();
// random number initialised
// random number has been initialised to the current time.
static int random(int lower, int upper);
// this function will return a positive random number within a specific lower and
// upper boundary.
};
Main.cpp 文件
#include <iostream>
#include <cstdlib>
#include <ctime>
#include <cmath>
#include <iomanip>
using namespace std;
// Include header files
#include "Circle.h"
#include "Random.h"
int main()
{
// Instantiate myCircle object
//Circle myCircle;
// Array 1
// an array of five circles objects where radius is set using the random number
// provided by the random class utilising the parameterised constructor
int CircleArrayOne [5]; // store the numbers
const int NUM = 5; // Display 5 random numbers
srand(time(NULL)); // seed the generator
// populate the array by calling the random function from the random class
// within the lower and upper bounds
for(int x = 0; x < NUM; ++x)
{
CircleArrayOne[x] = Random::random(1, 40); // assumed 0 and 40 as the bounds
}
// Below is the code I use to output the array to the screen to make sure
// that is output the correct number of values and it generate number between 1 and 40
// I am doing this to test the code above that populate the array within lower and upper
// bounds
cout << "Checking the radius in the Array 1." << endl;
for(int i = 0; i < NUM; ++i)
{
cout << CircleArrayOne[i] << endl;
}
// Array 2
// a second array of five circles objects where radius is set using the random number
// provided by the random class utilising the setRadius method
float CircleArrayTwo [5]; // store the numbers
const int Number = 5; // Display 5 random numbers
srand(time(NULL)); // seed the generator
// populate the array with random numbers
for(int i = 0; i < Number; ++i)
{
CircleArrayTwo[i] = rand()%100;
}
// Below is the code I use to output the array to the screen to make sure
// that is output the correct number of values and it generate random values
cout << "Checking the radius in the Array 2." << endl;
for(int i = 0; i < Number; ++i)
{
cout << CircleArrayTwo[i] << endl;
}
// Display the area of each Circle within each array using getArea()
cout << "\nThe area of each circle within array 1: " << endl;
cout << "\nThe area of each circle within array 2: " << endl;
// Display a message that indicates which set of circle has the largest
// combined area
cout << "\nArray: " << "had the largest combined area." << endl;
// Display a message that indicates which set contains the circle
// with the largest area
cout << "\nArray: " << "contain the circle with the largest area.\n" << endl;
system("PAUSE");
return 0;
}
// Calling Circle(float r) from Circle Class
Circle::Circle(float r)
{
if (r<=0)
{
cout << "An invalid radius has been detected." << endl;
cout << "The radius has been set to 1.0" << endl;
Radius = 1.0;
}
else
Radius = r;
}
// Calling getArea() from Circle Class
float Circle::getArea()
{
// Area = pi * radius * radius
return 3.14 * Radius * Radius;
}
// Calling setRadius(float r) from Circle Class
void Circle::setRadius(float r)
{
rand()%100;
Radius = r;
}
// Calling getRadius() from Circle Class
float Circle::getRadius()
{
return Radius;
}
// Calling random(int lower, int upper) from Random Class
int Random::random(int lower, int upper)
{
int range = upper - lower + 1;
return (rand() % range + lower);
}
// Calling initialiseSeed() from Random Class
void Random::initialiseSeed()
{
srand((unsigned int)time(0));
rand()%100;
}
如何使用getArea()函数获取每个数组中每个圆的面积