Thread: how to scanf a global variable outside the main ?

Hello
the problem that I want to make an array " vertextDegree [nbColours] " with " nbColours " elements in it ,but the "nbColours" unknown and I have to get it get it from a file .
look at the code
so what can I do to solve this problem ?

Code:

	

		

			

			
				
int nbEdges,nbVetices, nbColours ;
typedef struct st_graphVertex 
{
    int index;
    int colour;
    int val ;
    int vertexDegree[nbColours]; // it won't work because nbColours unknown     
                                               //  here and I want get it from file in the main
   struct st_graphVertex *next; 
    t_edgeList *out;
}t_grapheVertex;

			
		
	

Make vertexDegree a pointer, and use malloc() to allocate memory sufficient for an array of nbColours ints. Preferably store nbColours as a member of the struct, so you have a record of the allocated size.

Beyond that, it is a case of writing actual code for a main() function (!), writing code to read required values.

Well you start with this

Code:

typedef struct st_graphVertex 
{
    int index;
    int colour;
    int val ;
    int *vertexDegree;
   struct st_graphVertex *next; 
    t_edgeList *out;
}t_grapheVertex;

Then when you do know what is stored in nbColours, you can do this.

Code:

foo->vertexDegree = malloc( nbColours * sizeof(*foo->vertexDegree) );

Then you can access foo->vertexDegree[0] etc up to the limit you've set.