functions

This is a discussion on functions within the C++ Programming forums, part of the General Programming Boards category; i am having trouble with the divide function in the main. any help would be great. Code: #include <iostream> #include ...

  1. #1
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    functions

    i am having trouble with the divide function in the main. any help would be great.


    Code:
    #include <iostream>
    #include "fun.h"
    using namespace std;
    double divide (double num1, double num2);
    int main()
    
    {
    	double a, b, c;									//declares variables
    	cout<<"Enter two numbers:";							//displays output	
    	cin>>a>>b;									//gets input
    	cout<<endl;									//ends line
    
    	/**************************************
    	*  Adds the value of a and b          *
    	*  @param a  a double                 *
    	*  @param b  a double 	              *
    	*  @return   the sum of the two inputs*
    	**************************************/
    	c=add(a,b);
    	cout<<"The sum of the two numbers is: " <<c;
    	cout<<endl;
    
    	
    	/***************************************
    	*  Subtracts the value of a and b      *
    	*  @param a  a double                  *
    	*  @param b  a double 	               *
    	*  @return   the diff of the two inputs*
    	***************************************/
    	c=subtract(a,b);
    	cout<<"The difference of the two numbers is: " <<c;
    	cout<<endl;
    	
    	
    	/******************************************
    	*  Mutiplies the value of a and b         *
    	*  @param a  a double                     *
    	*  @param b  a double 	                  *
    	*  @return   the product of the two inputs*
    	******************************************/
    	c=multiply(a,b);
    	cout<<"The product of the two numbers is: " <<c;
    	cout<<endl;
    
    	
    
    	/***************************************
    	*  Cubes the value of a and b          *
    	*  @param a  a double                  *
    	*  @param b  a double 	               *
    	*  @return   the cube of one input     *
    	***************************************/
    	c=cube(a);
    	cout<<"The cube of the first number is: " <<c;
    	cout<<endl;
    
    	
    	/***************************************
    	*  Cubes the value of a and b          *
    	*  @param a  a double                  *
    	*  @param b  a double 	               *
    	*  @return   the cube of one  input    *
    	***************************************/
    	c=cube(b);
    	cout<<"The cube of the second number is: " <<c;
    	cout<<endl;
    
    
    	
    
    
    	double divide (double num1, double num2)
    	{
    		double total;  
    		total = num1 / num2;
    		return total;
    	}
    		
    
    
    
    return 0;
    }

  2. #2
    Senior Member joshdick's Avatar
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    Define that function outside of your main() function.
    Ex:
    Code:
    #include <iostream>
    using namespace std;
    
    void foo();
    
    int main()
    {
      //
      //
      return 0;
    }
    
    void foo()
    {
      cout << "foo" << endl;
    }
    FAQ

    "The computer programmer is a creator of universes for which he alone is responsible. Universes of virtually unlimited complexity can be created in the form of computer programs." -- Joseph Weizenbaum.

    "If you cannot grok the overall structure of a program while taking a shower, you are not ready to code it." -- Richard Pattis.

  3. #3
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    is there any way to get this to work inside the main.

  4. #4
    unleashed alphaoide's Avatar
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    That would be non-function version
    Code:
    int main() 
    {
       // the rest of the code
    
       double total;  
       total = num1 / num2;
    		
       return 0;
    }
    source: compsci textbooks, cboard.cprogramming.com, world wide web, common sense

  5. #5
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    is it possible to do this as a function in the main?

  6. #6
    unleashed alphaoide's Avatar
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    Originally posted by bj31t
    is it possible to do this as a function in the main?
    Nop, can't declare a function inside a function, including main
    source: compsci textbooks, cboard.cprogramming.com, world wide web, common sense

  7. #7
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    thanks for the help

  8. #8
    Registered User jlou's Avatar
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    You can write the function outside of main and call it from inside main like you called multiply, cube, etc. That is how it is normally done.

  9. #9
    Hardware Engineer
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    Thumbs up Right!

    ...That is how it is normally done.
    Right! In fact, with most large programs, main() won't do anything except call other functions. You might have some "branching" logic (like if-statements and switch-statements), but all of your I/O, calculations, data manipulation, etc., would be done in functions.

  10. #10
    Carnivore ('-'v) Hunter2's Avatar
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    Keyword: large programs Just to clarify.
    Just Google It. √

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