Write your own replacements for the memory allocation/deallocation
routines malloc() and free(). Name these two new functions NewMalloc()
NewMalloc() allocates memory for each call from
an array of fixed size. This array is an array of 50,000 bytes. All the
data structures that you declare to manage this 50,000 bytes memory
area must reside within that memory area.
The memory allocated using NewMalloc() can be freed with NewFree().