access violation error

[Michael P.]

Koroskin Denis Wrote:

> On Thu, 14 Aug 2008 01:23:05 +0400, Wyverex <wyverex.cypher at gmail.com>  
> wrote:
> 
> > Michael P. wrote:
> >> /* junior304.d
> >> 2008 junior problem 3
> >> Smile with similies
> >> Ask for 2 numbers; the number of adjectives and nouns
> >> After you get the numbers and nouns and adjectives, out all possible  
> >> similies
> >> August 12th, 2008 */
> >>  //Imports
> >> import std.stdio;
> >>  /*****
> >> *Main*
> >> *****/
> >> void main()
> >> {
> >> 	int numberOfAdjectives;
> >> 	scanf( "%d", &numberOfAdjectives );
> >> 	int numberOfNouns;
> >> 	scanf( "%d", &numberOfNouns );
> >> 	
> >> 	char[][] adjectives; //array of strings to hold the adjectives
> >> 	adjectives.length = 6; //max number that user enters is 5, 6 to be  
> >> safe 	char[][] nouns; //same as above, but for nouns
> >> 	nouns.length = 6; //same as adjectives reason
> >> 	
> >> 	//get adjectives first
> >> 	for ( int i = 0; i < numberOfAdjectives; i++ ) //get the specified #  
> >> of adjectives
> >> 	{
> >> 		scanf( "%s", &adjectives[ i ] );
> >> 	}
> >> 	
> >> 	//now get the # of nouns specified
> >> 	for ( int i = 0; i < numberOfNouns; i++ )
> >> 	{
> >> 		scanf( "%s", &nouns[ i ] );
> >> 	}
> >> 	
> >> 	//print out all possible similies
> >> 	for ( int i = 0; i < numberOfAdjectives; i++ )
> >> 	{
> >> 		for ( int j = 0; j < numberOfNouns; j++ )
> >> 		{
> >> 			//for every adjective, place a noun after and turn it into a similie
> >> 			writefln( "%s as %s", adjectives[ i ], nouns[ j ] );
> >> 		}
> >> 	}
> >> }
> >>   I get an accessviolation when I enter the last 2 for loops; any  
> >> reason why?
> >>  Input is:
> >> 3
> >> 2
> >> Easy
> >> Soft
> >> Smart
> >> pie
> >> rock
> >>  error!
> >
> Your code is seriously broken!
> 
> The following line is wrong, for example:
> > scanf( "%s", &nouns[ i ] );
> 
> What are you doing here? Are you out of your mind? You are passing a  
> pointer to a char[]* to a function that accept a char*. Your array will be  
> overwritten with whatever you will type. It is wrong, wrong, wrong!
> 
> I think that you don't understand something. First of all, what is a  
> char[]? It is a struct that consists of a array size and a pointer:
> 
> struct CharArray {
>     size_t size;
>     char* ptr;
> }
> 
> typeof(nounts[i]) is a char[], typeof(&nouns[i]) is char[]*. You pass this  
> pointer to a function that accepts a pointer to a preallocated buffer for  
> a string to be written to.
> 
> A quick fix would be to:
> 1) allocate a buffer:
> nouns[i] = new char[64];
> 2) pass a pointer to the preallocated buffer:
> scanf("%s", nouns[i].ptr);
> 
> A good fix would be to use readf instead. I didn't use it, but this should  
> be sufficient:
> readf("%s", &nouns[i]);
> 
> 
> > quick fix is to use printf
> > printf( "%s as %s", &adjectives[ i ], &nouns[ j ] );
> >
> > i think (not sure don't really use phobos that much) scanf doesn't  
> > return strings in a format writef likes...
> >
> > I though theres a readf but cant find documentation on it...
> 
> Test before posting, please!


Sorry I made you angry...

I changed all the scanfs to din.readfs and everything worked okay... does that solve my passing a pointer to a string to function that accepts a pointer to a char?
I guess I should check the documentation for some stuff like that.