我输入的坐标对了，但不是长方形它也会输出长和宽来，怎么改才能使当它不是长方形的时候就不输出长和宽，是长方形或正方形的时候才输出？最好可以贴出改之后的代码看看，不要回答没有用的东西

Question

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

class Rectangle
{
 public:
  Rectangle(float *x,float *y)
  {
   setCoordinate(x,y); 
  }
  
  void setCoordinate(float *x,float *y)  //设置坐标 
  {
   for(int i=0;i<4;i++)
   {
    if((x[i]<=0.0)||(x[i]>20.0)||(y[i]<=0.0)||(y[i]>20.0)) 
    {
    cout<<"有错误,请重新输入\n"; 
    break; 
    }
    else
    X[i]=x[i];
    Y[i]=y[i];
   }
   
if(x[3]-x[2]==x[1]-x[0]&&y[3]-y[2]==y[1]-y[0])
{
if((x[1]-x[0])*(x[1]-x[0])+(y[1]-y[0])*(y[1]-y[0])+(x[3]-x[0])*(x[3]-x[0])+(y[3]-y[0])*(y[3]-y[0])==
(x[3]-x[1])*(x[3]-x[1])+(y[3]-y[1])*(y[3]-y[1]))
   cout<<"该四边形是长方形\n";
}
else
cout<<"该四边形不是长方形\n";
   }
  //获得长
  float getLength()                    
  {
   float length,temp1,temp2;
   temp1=pow((Y[1]-Y[0])*(Y[1]-Y[0])+(X[1]-X[0])*(X[1]-X[0]),0.5);
   temp2=pow((Y[2]-Y[1])*(Y[2]-Y[1])+(X[2]-X[1])*(X[2]-X[1]),0.5);
   if(temp1>temp2) 
       length=temp1;
   else
       length=temp2;
   return length;
  }
  //获得宽
  float getWidth()        
  {
    
   float width,temp1,temp2;
   temp1=pow((Y[1]-Y[0])*(Y[1]-Y[0])+(X[1]-X[0])*(X[1]-X[0]),0.5);
   temp2=pow((Y[2]-Y[1])*(Y[2]-Y[1])+(X[2]-X[1])*(X[2]-X[1]),0.5);
   if(temp1>temp2) 
       width=temp2;
   else
       width=temp1;
   return width;
  }
  //计算周长
  float getPerimeter()          
  {
   return (2*getLength()+2*getWidth());
  } 
  //计算面积 
  float getArea()           
  {
   return (getLength()*getWidth());
  } 
  //判断是否是正方形 
  void guessSquare()        
  {
   if((getWidth()==0)||(getLength()==0))
   cout<<"无法判断\n"; 
   
   else if(getWidth()==getLength())
   {
   cout<<"该图是正方形\n";
   }
   else  
   {
   cout<<"该图不是正方形\n";
   }  
  }
  
 private:
  float X[4],Y[4],*d; 
};

int main()
{
 int i;
 float x[4],y[4];
 float *p=x,*q=y;  //指针指向数组
 cout<<"从长方形左上角开始顺时针输入坐标（坐标在第一象限且小于等于20\n";
 for (i=0;i<4;i++)              
 {
 cin>>x[i];//输入数组
 cin>>y[i];
 }
  Rectangle nb(p,q);//给类成员
 cout<<"长为："<<nb.getLength()<<endl;
 cout<<"宽为："<<nb.getWidth()<<endl;
 nb.guessSquare();
 return 0; 
}

Answer 1

运行结果：
是长方形的结果：

不是长方形的结果：

代码：

#include <iostream>
#include <math.h>
using namespace std;
class Rectangle
{
public:
    Rectangle(double* x, double* y)
    {
        width = 0;
        length = 0;
        setCoordinate(x, y);
    }

    void setCoordinate(double* x, double* y)  //设置坐标 
    {
        for (int i = 0; i < 4; i++)
        {
            if ((x[i] <= 0.0) || (x[i] > 20.0) || (y[i] <= 0.0) || (y[i] > 20.0))
            {
                cout << "有错误,请重新输入\n";
                break;
            }
            else
                X[i] = x[i];
            Y[i] = y[i];
        }

        //左顶点x[0],y[0],右顶点x[1],y[1] , 0 1 2节点构成直角三角形
        double length1 = (x[1] - x[0]) * (x[1] - x[0]) + (y[1]-y[0]) * (y[1]-y[0]);
        double width1 = (x[1] - x[2]) * (x[1] - x[2]) + (y[1] - y[2]) * (y[1] - y[2]);
        double duijiaoxian = (x[2] - x[0]) * (x[2] - x[0]) + (y[2] - y[0]) * (y[2] - y[0]);
        //0 2 3节点构成直角三角形
        double width2 = (x[0] - x[3]) * (x[0] - x[3]) + (y[0] - y[3]) * (y[0] - y[3]);
        double length2 = (x[2] - x[3]) * (x[2] - x[3]) + (y[2] - y[3]) * (y[2] - y[3]);

        if (length1 == length2 && width1 == width2 && length1 + width1 == duijiaoxian)
        {
            isRectangle = 1;
            if (length1 > width1)
            {
                length = sqrt(length1);
                width = sqrt(width1);
            }
            else
            {
                length = sqrt(width1);
                width = sqrt(length1);
            }
            cout << "该四边形是长方形\n";
        }
        else
        {
            isRectangle = 0;
            cout << "该四边形不是长方形\n";
        }
            
        

    }
    //获得长
    double getLength()
    {
        return length;
    }
    //获得宽
    double getWidth()
    {
        return width;
    }
    //计算周长
    double getPerimeter()
    {
        return (2 * getLength() + 2 * getWidth());
    }
    //计算面积 
    double getArea()
    {
        return (getLength() * getWidth());
    }
    //判断是否是正方形 
    void guessSquare()
    {
        if ( width == 0 || length == 0)
            cout << "无法判断\n";

        else if ( length == width)
        {
            cout << "该图是正方形\n";
        }
        else
        {
            cout << "该图不是正方形\n";
        }
    }

private:
    double X[4], Y[4], width,length;
    int isRectangle; //是否是长方形标记
};
int main()
{
    int i;
    double x[4], y[4];
    double* p = x, * q = y;  //指针指向数组
    cout << "从长方形左上角开始顺时针输入坐标（坐标在第一象限且小于等于20\n";
    for (i = 0; i < 4; i++)
    {
        cin >> x[i];//输入数组
        cin >> y[i];
    }
    Rectangle nb(p, q);//给类成员
    cout << "长为：" << nb.getLength() << endl;
    cout << "宽为：" << nb.getWidth() << endl;
    nb.guessSquare();
    return 0;
}