Identifier not found

[CrypticA1]

Write your question here.

 #include <iostream>
Using namespace std;
int main() 
{
int height;
int base;

cin>> base >> height;
cout <<"the area is" << area (base, height);

system ("pause") ;
return 0 ;

} 

float area(int a,  int b) 
{

float area;

area=. 5*a*b;

return area;

} 


I keep getting an error that the "idsntifier is not found".  

[Arslan7041]

You need to include the prototype of the area function above main. The prototype of a function is simply its return type, followed by function name, followed by the parameter types (separated by commas) in parenthesis. Prototypes also end with a semi-colon.

Line 2: "Using namespace std" should be with a lowercase 'u'.

Line 21: Remove the dot after the equals sign.

[Kevin C]

The compiler doesn't know about the name 'area' untill you declare it.

Two possible solutions:
1) Define the area function before the main function. Every definition is also a declaration
2) If you know how to declare a function, declare the area function before the main function.

[CrypticA1]

Tha ks for the replies and just to be clear I actually typed this in the back of a bus... Getting a little Car sick. So some of the mistakes may have just been errors when I was typing my notes on my phone. Anyway could you possibly show me how to define a function in this scenario?

[E0p9LyTq]

When using a user created function you need to either define the entire function before you can use it, or declare a prototype of the function before use.

Since you are returning a float value from your function why not make all your variables floats. Less conversion errors to possibly deal with.

#include <iostream>

float area(float a,  float b);

int main()
{
   float height;
   float base;

   std::cout << "Enter the base and the height: ";
   std::cin >> base >> height;

   std::cout << "\nThe area is " << area(base, height) << std::endl;

   return 0;
}

float area(float a,  float b)
{
   float area;

   area = .5 * a * b;

   return area;
}

You could also simplify the area function to something like this:

float area(float a,  float b)
{
   return (.5 * a * b);
}

Arslan7041 wrote:

Line 21: Remove the dot after the equals sign.

That "dot" is a decimal point, misplaced.

[Kevin C]

When using a user created function you need to either declare the entire function before you can use it, or provide a prototype of the function before use.

I know what you ment, but please try to use accurate terminology in order not to confuse a beginner even more.

So, he either needs to DEFINE the entire function before use or he needs to provide a prototype which will declare the function.

Anyway could you possibly show me how to define a function in this scenario?

You have already defined it in your original post. Just move the definition of area function before the definition of the main function.

[Arslan7041]

That "dot" is a decimal point, misplaced.

Oh, I see. My mistake.

[Kevin C]

I actually typed this in the back of a bus... Getting a little Car sick.

Looking at phone, computer screen, a television, or reading a book in a bus will make it worse.

Look outside!!!