Load a map through an NSString - iphone

Question

I am working on a game that requires a tile map saved in multidimensional array. In my game I have all of these maps made that are NSStrings with all the saved values needed, I'm looking to save all the 256 values of the NSString into an int 16x16 multidimensional array.
Here is my current code however it doesn't work
-(void)LoadMap:(NSString*)mapString
{
for(int h = 0; h < kMapSize; h++)
{
for(int w = 0; w < kMapSize; w++)
{
map[w][h] = [[mapString substringWithRange:NSMakeRange((h)+(w*kMapSize), 1)] intValue];
}
}
}
Any help would be great thankyou :)

Answer 1

There are two potential errors:
kMapSize is possibly not equal to 16. This variable has a misleading name since the casual reader would think it should be 256. Perhaps rename it kMapWidth.
mapString is possibly not 256 characters long. You might want to check [mapString length] at the beginning of LoadMap.

Answer 2

Below code works without problem. Maybe the second row is the reason of error.
// initial data
NSInteger kMapSize = 3;
char map[3][3]; <-- this row ?
NSString *mapString = #"000111222";
// put initial data into 'map' array
for(int h = 0; h < kMapSize; h++) {
for(int w = 0; w < kMapSize; w++) {
map[w][h] = [[mapString substringWithRange:NSMakeRange((h)+(w*kMapSize), 1)] intValue];
}
}
// confirm whether the data is stored successfully
for (int h = 0; h < kMapSize; h++) {
for (int w = 0; w < kMapSize; w++) {
NSLog(#"%d", map[w][h]);
}
}