Thread: Can someone please help me with a short segment of code I am having trouble with?

Originally Posted by matthayzon89

Hello,
Can someone please help me understand why my function is not working?
I tried a few different things but below is my best attempt which is still not working like it is suppose to:/

Can u be more specific?

Can someone please help me understand how the function code for the functions listed in the header file above can be coded into such a program such as the one below:

I am not looking for solutions, just an explanation... The reason why I am confused is because the program below was given to us with the program assignment instructions...


Do you guys think I am just suppose to use the program below as a structure suggestion and simply replace each line below with a line of code that I created that completes the same objectives as the lines below suggest, or am i suppose to run the code below at the end, just as it is, and have it work successfully?

Code:

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <time.h>
#include "frameworknew.h"


int main () {

int guess1, guess2, guess3, guess4;


if ((guess1 == 0 > 5) && (guess2 == 0 > 5) && (guess3 == 0 > 5) && (guess4 == 0 > 5)); 
{

    // Stores the real answer and the user's board, respectively.
    int answer[NUM_PEGS];
    int board[NUM_PEGS];
    
    // Set everything up.
    int num_turns = 0;    
    fillBoard(answer);
    greeting();
    int start = time(0);
    
    // Loop through each turn, ending at 10 moves or a win.
    do {
        
        // Read in the user's guess.
        getUserGuess(board);
        
        // Figure out the number of matches.
        int num_perfect = numPerfectMatches(board, answer);
        int num_imperfect = numWrongPlaceMatches(board, answer);
        
        // Update for this turn.
        printf("You have %d perfect matches and %d imperfect matches.\n", num_perfect, num_imperfect);
        num_turns++;
        
    } while (num_turns < MAX_TURNS && numPerfectMatches(board, answer) < NUM_PEGS);
    
    // Winning case.
    if (numPerfectMatches(board, answer) == NUM_PEGS) {
        int end = time(0);
        printWinner(num_turns, end-start);
    }
    
    // Losing case.
    else {
        printf("Sorry, you have exceeded the maximum number of turns. You lose.\n");
        printf("Here is the winning board: ");
        printArray(answer, NUM_PEGS);
        printf("\n");
        }
}


system ("PAUSE");
return 0;

}

First, I haven't read all of this thread, just your last post. My guess is that you are given the file above (obviously), that you've posted, and are also given "frameworknew.h", and what you have to do is write a file "frameworknew.c" that implements all of the functions listed in "frameworknew.h". So, say you are given "foo.h" that looks like

Code:

int someVariable = 1234;

int getRandomNumber();

void foo(char*);

// and more function prototypes

then you have to write the file "foo.c", which implements all of those functions, like

Code:

#include "foo.h"

int getRandomNumber()
{
   return 42;
}

void foo(char * str)
{
   if ( str != NULL )
   {
      printf("%s\n", str);
   }
}

So, if my assumption above is correct, then you have to create the corresponding ".c" file, implementing each function prototype in the ".h" file.

However, if this is an assignment, I imagine you are told exactly what to do, and you shouldn't really have to "guess" what the goal is. Try and clarify with the appropriate person, if this is the case.

Hey, Thank you for the response

...so if I need to write a .c file that implements each function prototype in the .h file why do you think the code one post above yours was given?


so If i am understanding correctly I would end up with 3 files total, 1) framework.h 2)framework.c (implementing each function) and 3) the .c code that is located one post above yours?

why do you think this was included in the assignment?

Are you asking why the ".h" file was included? If so, the header files is basically the "interface". It says "I have these global variables (if any), and these functions named X, Y, Z, which take these types of arguments, and return this type of variable." Then the program that uses this (the program you posted above, with "main") just needs to refer to the header file, or "interface". It just needs to know that "Oh, there's a function named "getRandomVariable" that I can use." This prevents the caller from having to know or care about the implementation of this function. It just needs the functions signature (return type, name, type of parameters). It doesn't need to know how it does whatever it does. It just needs to know that it will "somehow" be done. You can kinda think of the header file as a "blackbox" to the ".c" code.

Your instructor, or whoever, gave you the ".h" file and the "main" program so that each student (I assume) has to implement the same functions, without modifying any of the given .h or .c code. You may implement the functions differently than some other person. However, all that matters is that the function does what it should do. Again, how it does it is transparent to the caller/main program.

In short, the ".h" file specifies the requirements, what you must implement. If you don't implement something, or something correctly, then the program will either not compile at all, or not run correctly.

For example, when you "#include <stdio.h>" to use, say, "printf", you don't have to go look at the code or know anything about the implementation of "printf" function. You just need to know how to use it, and expect it will do what it says it will do (i.e. print something).

EDIT:

so If i am understanding correctly I would end up with 3 files total, 1) framework.h 2)framework.c (implementing each function) and 3) the .c code that is located one post above yours?

Yes. You, I believe, are given the two files, and you must write "framework.c", for a total of 3 files.

So once I am done writing the code for each function in the framework.c file... will using a function call such as "#include "framework.h" be good enough for my guessinggame.c program to understand what each function in my header file means?


Thank you so much by the way, I am finally beginning to understand what needs to be done THANK YOU

The "#include "framework.h"" line just tells the compiler to "look" into that file, so it knows what variables it declares, as well as what the prototypes of the functions in it. These prototypes are basically just "promises" that somewhere these functions will actually be implemented. To the compiler, all it needs to know is its prototype, like

Code:

int foo(char* bar);

is a function prototype, and gives the compiler all the information it needs about this function.

When you compile the program given to you, the compiler will "look" at the ".h" file you include, so it knows what functions you promised to implement. When the compiler later "link"s the code, it is actually expecting you to come through on your promise that you will implement these functions. So, it is looking for the actual ".c" code of these functions. If it isn't given, you will see compiler errors like "undefined reference", because you promised to implement a function, then never did (according to the compiler).

In short, in addition to the "#include" line, when you compile you have to also tell the compiler where the code is, so you need to pass two files, each of your ".c" files. If you use gcc, you might do something like

Code:

gcc mainProgram.c framework.c -o myProg

If you use a different compiler, then look around in it's documentation for compiling multiple files. I think it will "automatically" figure out what files to compile, and compile them, but I'm not sure.

EDIT: Also, the "#include" isnt a "function call". Its a "preprocessor directive", that you can read about if you want.