graph issue

[momotaro]

 node *BuildGraph() 
 
{
 
int range, vehicules, i, j, k;
 
char ch;
 
vehicule *V = NULL,
 
*E = NULL;
 
node *N = NULL;
 
//edge *NewEdge;
 
FILE *InputFile = fopen("data.txt", "r");
 
if(!InputFile)
 
ERROR("FILE COULD NOT BE OPENED");
 
else
 
{
 
fscanf(InputFile, "%d %d", &vehicules, &range);
 
for(i = 0; i < vehicules; i++)
 
{
 
fscanf(InputFile, "%d %d", &vehicules, &range);
 
for(k = 0; k < i; k++)
 
for(ch = getc(InputFile); ch != '\n'; ch = getc(InputFile))
 
V = CreatVehicule();
 
fscanf(InputFile, "%s %d %d", V->CarId, &V->x, &V->y);
 
N = InsertVehicule(N, V);
 
for(j = 0; j < vehicules; j++)
 
{
 
fseek(InputFile, 0, 0);
 
fscanf(InputFile, "%d %d", &vehicules, &range);
 
E = CreatVehicule();
 
fscanf(InputFile, "%s %d %d", E->CarId, E->x, E->y);
 
E->distance = Distance(V->x, V->y, E->x, E->y);
 
if(E->distance <= range)
 
{
 
N = InsertEdge(N, E);
 
}
 
}
 
//break;
 
}
 
}
 
fclose(InputFile);
 
return N;
 
}
 
 

am having those errors:
[size=1]First-chance exception at 0x10295db1 (msvcr90d.dll) : 0xC0000005: Access violation writing location 0x00000000.

Unhandled exception at 0x10295db1 (msvcr90d.dll) : 0xC0000005: Access violation writing location 0x00000000.

[/size]

[Ganon11]

Sounds to me like there is a pointer error going on. Either you are trying to access a pointer that has been freed, or that you are making a pointer point somewhere that hasn't been allocated. Check any part of your program that uses pointers, and make sure you aren't doing things like exceeding the bounds of an array or using it after a free() statement.

[weaknessforcats]

Have you stepped thgrougfh the code using your debugger???

If not, learn how to use the debugger. You can pinpoint the failure exactly.