there are illogical results by using try and catch block

[batoool]

there are illogical results by using try and catch block

#include<iostream>
using namespace std;
 
class Circle_computations
{
 
public:
    double area,circumference,radius,pi;
 
public:
 
 
 Circle_computations()
{
 }    
  Circle_computations(double radi)
{
pi = 3.14;
radius=radi;
 
 
}
 
double c_area()
{
 
area = pi*radius*radius;
return area;
 
}
 
double c_circumferunce()
{
 
circumference =2*pi*radius;
return circumference;
 
}
 
};
 
class Cylinder:public Circle_computations
{
 
protected:
    double height,volume,cyarea;
 
public:
Cylinder(double r, double h) :
    Circle_computations(r)
{
    height = h;
}
 
 
    double cy_area()
{
    cyarea=(2 * (Circle_computations::c_area()))+( c_circumferunce()* height) ;
 
cout<<cyarea;
}
 
 
double c_volume()
{
    volume = (Circle_computations::c_area())* height;
 
    return volume;
cout<<volume;
}
 
 
};
 
 
int main()
 
{
double r,heigh_t;
cout<<"**Please Enter The Radius First** \n";
cin>> r;
cout<<"**Please Enter The height** \n";
cin>>heigh_t;
 
try
{
if(r||heigh_t<=0.0)
{
throw "PLESE ENTER double NUMBERS";
 
 
}
}
 
catch (char* strException)
{
    cerr << "Error: " << strException << "\n";
}
 
Circle_computations  compute(r);
Cylinder computecylider(r,heigh_t);
 
cout<<"****The cylinder surface  Area   is****\n";
cout<<computecylider.cy_area();
 
cout<<"\n";
cout<<"****The cylinder volume   is****\n";
cout<<computecylider.c_volume();
 
cout<<"\n";
 
 
 
}

[Banfa]

try
{
  if(r||heigh_t<=0.0)
  {
    throw "PLESE ENTER double NUMBERS";
  }
}
catch (char* strException)
{
  cerr << "Error: " << strException << "\n";
}

Line 3, strange construct this will through an exception if r is any non-zero value or heigh_t is less than 0 did you mean if((r <- 0.0) || (heigh_t<=0.0)) i.e. throw if either variable is less than 0?

Line 5, do not throw a string, throw a std::exception or any sub-class of it defined in stdexcept.

Whole code, very strange indeed why are you using a exception for this when it is functionally equivilent to

if(r||heigh_t<=0.0)
{
  cerr << "Error: PLESE ENTER double NUMBERS\n";
}

And finally don't use '\n' use std::endl, i.e.

if(r||heigh_t<=0.0)
{
  cerr << "Error: PLESE ENTER double NUMBERS" << std::endl;
}