这是我多次重写的代码，只是无法正常工作。应该很简单，就是不得到感谢。 C ++
对于不同的公式，将需要执行一些不同的函数计算，这些计算要么找到值的平方根，要么找到加到幂的数字，或者两者兼而有之。
必须使用cmath库函数“ pow”和/或“ sqrt”进行计算。与此同时，您将使用acos（-1）进行估算。此值必须使用常量变量保存。
#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>
#define PI 3.1415926 //PI
using namespace std;
int option;
char countine = 'y';
double coneVolume;
double sphereVolume;
double octagonArea;
double pointDistance;
//Calculations functions
void cone(double r, double h)
{
cout <<"Volume = " << (1/3) * PI * pow ( r, 2 ) * h;
}
void sphere (double r)
{
cout << "Volume + " << (4/3) * pow ( r, 3 ) * PI;
}
void octagon (double s)
{
//cout << "Area = " << 2 (1 + sqrt (2))- pow ( s, 2);
}
void point (double x1, double x2, double y1, double y2)
{
//cout << "distance = " << ((sqrt pow((x2-x1),2) + pow((y2-y1),2);
}
int main ()
//The menu choices will be the following four calculations:
//Find the volume of a cone
//Find the volume of a sphere
//Find the area of octagon
//Find the distance between two points
{
char countinue = 'y';
while (countinue = 'y')
cout << "select program to run " <<endl;
// volume of cone
cout << "1.Find the volume of a cone "<<endl;
// volume of sphere
cout << "2.Find the volume of a sphere" <<endl;
// area of octagon
cout << "3.Find the Area of a octagon " << endl;
// distance of two points
cout << "4.Find the distance between two points " << endl;
cout << " Enter option ? ";
cin >> option;
switch (option)
{
// volume of cone
case 1:
//using namespace std;
option = true;
double r,h;
cout<<"\nEnter cone radius: ";
cin>>r;
cout<<"\nEnter cone height: ";
cin>>h;
cone = (r, h);
cout<<"\nThe volume of the cone is: "<<setprecision(2)
<<fixed<<cone<<endl<<endl;
break;
//volume sphere
case 2:
option = true;
double r;
cout<<"\nEnter sphere radius: ";
cin>>r;
sphere = (r);
cout<<"\nThe volume of the sphere is: "<<setprecision(2)
<<fixed<<sphere<<endl<<endl;
break;
//area octagon
case 3:
option = true;
double octagon;
cout<<"\nEnter the length of one side: ";
cin>>s;
octagon = octagonArea (sideLength);
cout<<"\nThe area of the octagon is: "<<setprecision(2)
<<fixed<<octagon<<endl<<endl;
break;
//distance
case 4:
option = true;
double distance;
cout<<"\nEnter the first x and y coordinates: ";
cin>>x1>>y1;
cout<<"\nEnter the second x and y coordinates: ";
cin>>x2>>y2;
distance = pointDistance (x1, x2, y1, y2);
cout<<"\nThe distance between points ("<<x1<<", "<<y1<<") and ("
<<x2<<", "<<y2<<") is: "<<setprecision(4)<<fixed<<distance<<endl<<endl;
break;
}
return 0;
}
答案 0 :(得分：0)
以上评论当然是正确的。
此外，我发现了其他问题，例如：
这是我获得的代码，似乎可以正常工作。请不要简单地复制它，而是尝试理解修改。
#include <iostream>
#include <iomanip>
#include <string>
#include <cmath>
static double const PI = acos(-1);
using namespace std;
//Calculations functions
double cone(double r, double h)
{
return (1.0/3.0) * PI * pow ( r, 2) * h;
}
double sphere (double r)
{
return (4.0/3.0) * pow ( r, 3 ) * PI;
}
double octagon (double s)
{
return 2 * (1 + sqrt (2)) * pow (s, 2);
}
double pointDistance (double x1, double x2, double y1, double y2)
{
return sqrt(pow((x2-x1),2) + pow((y2-y1),2));
}
int main ()
//The menu choices will be the following four calculations:
//Find the volume of a cone
//Find the volume of a sphere
//Find the area of octagon
//Find the distance between two points
{
char countine = 'y';
while (countine == 'y') {
int option;
cout << "select program to run " <<endl;
// volume of cone
cout << "1.Find the volume of a cone "<<endl;
// volume of sphere
cout << "2.Find the volume of a sphere" <<endl;
// area of octagon
cout << "3.Find the Area of a octagon " << endl;
// distance of two points
cout << "4.Find the distance between two points " << endl;
cout << " Enter option ? ";
cin >> option;
switch (option)
{
// volume of cone
case 1:
{
double r,h;
cout<<"\nEnter cone radius: ";
cin>>r;
cout<<"\nEnter cone height: ";
cin>>h;
double volume = cone(r, h);
cout<<"\nThe volume of the cone is: "<<setprecision(2) <<fixed<<volume<<endl<<endl;
}
break;
//volume sphere
case 2:
{
double r;
cout<<"\nEnter sphere radius: ";
cin>>r;
double volume = sphere(r);
cout<<"\nThe volume of the sphere is: "<<setprecision(2) <<fixed << volume << endl << endl;
}
break;
//area octagon
case 3:
{
cout<<"\nEnter the length of one side: ";
double s;
cin>>s;
double area = octagon (s);
cout<<"\nThe area of the octagon is: "<< setprecision(2) <<fixed << area << endl << endl;
}
break;
//distance
case 4:
{
double x1, y1, x2, y2;
cout<<"\nEnter the first x and y coordinates: ";
cin>>x1>>y1;
cout<<"\nEnter the second x and y coordinates: ";
cin>>x2>>y2;
double distance = pointDistance (x1, x2, y1, y2);
cout<<"\nThe distance between points ("<<x1<<", "<<y1<<") and (" <<x2<<", "<<y2<<") is: "
<<setprecision(4) << fixed << distance <<endl<<endl;
}
break;
}
cout << "Do you want to continue?";
cin >> countine;
}
return 0;
}