C :: Dynamically Create A New Memo Structure To Hold Memorized Fib

I need to dynamically create a new Memo structure to hold memorized fib #'s.I have two structures:

Code:

typedef struct HugeInteger
{
//array to hold the digits of a huge integer
int *digits;
//number of digits in the huge integer
int length;
}

[code]....

am having trouble with initializing the struct inside of the new Memo, I need the digit fields to null and the length field to 0 to indicate that F[i] has not yet been memoized...I have F->digits and F->length in the for loop but this just simply doesn't work..