BMI计算

Question

我对C++非常陌生，我希望你们都能回顾一下我为一个程序编写的源代码，这个程序可以计算用户的体重指数，如果用户需要做额外的计算，可以将程序循环回起点。

#include <iostream>
#include <stdlib.h>
using namespace std;

float bmiNumber(float pounds, float inches) //BMI calculation
{
  return ((pounds/inches)*703);
  }

void chart(int mF)
{
     if(mF==2) {
 cout<<"\nHere is some info you might find useful...\n"
     <<"At the same BMI, women tend to have more body fat than men."<<endl
     <<"From cdc.gov\n"<<endl;
     }
}
void history()
{
 cout<<"Version History"<<endl;
 cout<<"\tVersion 1.0.1(05/18/2012)"<<endl
     <<"Optimized source code for better program flow,\nImproved calculation algorithms,\n"
     <<"Introduded looping capabilities for\nmultiple calculations without restarting the program."<<endl;
 cout<<"\tVersion 1.0.0(05/15/2012)"<<endl
     <<"Creation of the program, very rough outline of the basic structure."<<endl;
     system ("pause");
}

int main()
{
int changes;
int m;
m=1;

cout<<"Hello and welcome to the BMI Calculation Tool 1.0.1, or BMICT1.0.1 for short."<<endl;
cout<<"If you would like to see the changes from the previous version(1.0.0)\nplease press 3..."<<endl;
cout<<"If not press any other key.";
 cin>>changes;
 if(changes==3)
 {
               history();
               }
cout<<endl<<endl<<endl;               
cout<<"Why don't you first tell me a little bit about yourself,\nby answering just one simple question."<<endl;
cout<<"Are you a man or a woman?";


while(m==1)
{ 
cout<<"If you are a man, please press 1,\nif you are a woman, please press 2."<<endl;
cout<<"Please make your selection now..."<<endl;
 cin>>m;



 if(m==1)
 {
        cout<<"Our sources have indicated that you are in fact a man,\n" 
            <<"please check to confirm this and continue with the program"<<endl;
 }
 else if(m==2)
 {
     cout<<"Our sources have indicated that you are a woman,\n"
         <<"if this is true please continue with the program"<<endl;
}

  else
  {
      cout<<"You have entered an incorrect key..."<<endl;
      cout<<"The program will now close.\n";

      system ("pause");
      return 0;
}
      chart(m);

  float feet;
  float inch; 
  float totalinches;          
  cout<<"Please enter your height as follows..."<<endl;                 
  cout<<"Number of feet: "<<endl;
  cin>>feet;

  cout<<"\nNumber of inches: "<<endl;
  cin>>inch;

  totalinches=(feet*12)+inch;

 cout<<"Your total height in inches is: "<<totalinches<<endl;  
 float inchSqd;
 float lbs;
 float BMI;
 inchSqd=(totalinches*totalinches);
 cout<<"Please enter your weight in pounds: \n";
 cin>>lbs;
 cout<<"Okay, we will now calculate your BMI\n";            
 BMI=bmiNumber(lbs, inchSqd);                                    
  cout<<endl
  <<"Your Body Mass Index Number is: "<<BMI<<endl;

 cout<<endl<<"Once again your BMI is "<<BMI<<", and here is a chart for review."<<endl;
 cout<<endl
     <<     "\tWeight Status"<<endl
     <<" Below 18.5     Underweight"<<endl
     <<" 18.5 to 24.9   Normal"<<endl
     <<" 25.0 to 29.9   Overweight"<<endl
     <<" 30.0 and Above Obese"<<endl;
 cout<<"If you would like to make another calculation press 1, if not press 2..."<<endl;
 cin>>m;
 }

 cout<<endl<<"Thank you for using the BMICT1.0.1 and have a great day.\n";

system ("pause"); 
return 0;
}

Answer 1

我尽量不要重复太多@Konrad Rudolph的观点：

• 这里非常重要:清理凹痕。它到处都是，让你的代码很难为别人阅读。我甚至不知道你想要使用的缩进程度，但不管是哪一种，只要坚持那个。
• 703看起来像一个神奇的数字，应该是一个常量(使用const)。这将允许您在任何地方使用此值，而该值在此程序中的使用将是已知的。
• chart()似乎没有做任何有用的事情，它的名称在这里也没有多大意义，所以可以删除它。函数不应该只打印一些硬编码的文本，因为这不被认为是有用的工作。
• 您正在混合std::endl和"\n"，但是您确实需要后者，因为不需要特殊的刷新。
• 请注意，system("PAUSE")是纯Windows的，因此是不可移植的.如果您想要进行可移植的暂停，请执行类似于std::cin.get()的操作。它确实有一些不同的工作方式，但在这里使用仍然更好。

总的来说，由于缩进，仍然很难对此进行回顾，而且这里可能还有更多的内容可供讨论。把注意力集中在清理这件事上，它应该看起来更好。