Runtime error

[Mungovan]

Hi.
I have this c program that creates a bunch of structures and fills them. When I compile it it's grand.

But when I run the program it output the desired results but says:

"An application error has occured...

Exception: access violation (0xc0000005), Address (0x0040f490) "


Anyone have any ideas of what's goin on???


Thanks,
D

 

[sleipnir214]

Most likely you've done something untoward with pointers. ______________________________________________________________________
TANSTAAFL!

 

[dickiebird]

Post your code, please Dickie Bird
Honi soit qui mal y pense

 

[jmnagi]

hi ..

exceptions are almost always to do with accessing something outside of your process boundary.

could be your stack if you have one. {pointers} -> make sure what your indexes are accesssing .. have you allocated ENOUGH memory ?

br:

 

[Mungovan]

Hi.
Thanks for the help. I am using alot of pointers to structures etc. Basically this is the brunt of my code (leaving out all the usual parts):


typedef struct node_t {
int x;
int y;
} node;

node *grid[100][100]; // 2D matrix of "node" pointers





for (x=0; x < SIZE; x++) // Initialise all pointers to NULL
{
for (y=0; y < SIZE; y++){
grid[x][y] = NULL;
}
}




for (i=0; i < POPULATION; i++){ // for each &quot;node&quot;
do
{
positionX = (rand() % 100);
positionY = (rand() % 100);
} while (grid[positionX][positionY] != NULL);
// loop until you find an empty space on the matrix


nodeLocation = (node*)malloc(sizeof(node));
grid[positionX][positionY] = nodeLocation;

nodeLocation->x = positionX;
nodeLocation->y = positionY;


// finally I want to print out the results:
for (i=0; i < POPULATION; i++){
for (j=0; j < POPULATION; j++){
printf(&quot;%d\t%d\t&quot;,grid[j]->x, grid[j]->y)
}
}







Any Ideas???????

Thanks,
D

 

[JOLESEN]

Instead of this :
// finally I want to print out the results:
for (i=0; i < POPULATION; i++){
for (j=0; j < POPULATION; j++){
printf(&quot;%d\t%d\t&quot;,grid[j]->x, grid[j]->y)
}
}


do this :
// finally I want to print out the results:
for (i=0; i < SIZE; i++){
for (j=0; j < SIZE; j++){
printf(&quot;%d\t%d\t&quot;,grid[j]->x, grid[j]->y)
}
}

/JOlesen