Hey guys.. Im stucked at my final exam with this exercise

To create a class UnordArray which can store
a number of data (integers), the new
embedded data are placed at the end of the structure.
Create a class described by creating appropriate
header and implementation files, which contain
following data:

buffer, which is a sequence of integers in which
stored data.
numElem, which represents an integer which stores the number
the currently inserted in the data structure.
To define a constructor, which landed the initial
value of data member numElem. To define
following functions of the class members:

int size (), which returns the number of data
void insert (int val), which inserts the data value
val at the end of the structure.
boolean delete (int val), searching the structure and if
it does not contain data with a value val, returns false; in
Otherwise removes data with value val, January
terminator structure, and returns true.

int find (int val), searching through the structure if it
contains data with a value val, returns -1, otherwise January
Returns the value of the index which is the value val

void print (), prints the data structure in
order from beginning to end.
To create a file koristi.cpp, which will be demonstrated
use of the newly created class and all UnordArray
Its features members. When creating the class
It is forbidden to use ready-library classes and
functions (other than iostream).

I Tryed 1000 times to make it work but it's always says SOMETHING MISSING!!!!
Can u give me a hand here pls? ... Maybe some 1 can wrote some part of it.. or anything ? Pls guys , let's do it :S
Thank you