Stack :Urgent...

Hi ,

I am having some problems with stacks. I am debugging it.

Is this the way to create stacks?

typedef struct numbers{
int num1;
int num2;
}NUM;

typedef struct stack
{
    NUM *rows;
    int n;
    int topofstack;
}STA;

in create function..

s->n=10;
s->topofstack=0;
s->rows=malloc(s->n*sizeof(NUM *));

in push function..

s->topofstack+=1;
s->rows[s->topofstack].num1=0;
s->rows[s->topofstack].num2=10


this is where i think the problem is ...
in the create function, i have malloced an array of pointers...
now here, do i malloc for an item ?or this is fine?