Exercise 2 – Implementing a Heap
This exercise is to be done during your week 3 laboratory class. When you complete the exercise
show your work to your lab tutor to have your work marked. The marking is based mainly on correct
implementation and code readability. You should implement your code in one file (e.g. ex2.cpp,
ex2.c, ex2.java). Make sure your program has a header comment block containing the name of the
exercise, your name and your student login (e.g. jfk01). You may implement your solution in C, C++,
java or Python.
For this exercise you are to implement a heap, using an array as shown in the lectures. The heap will
be built by repeatedly:
1. Reading an input from a file (in this case an integer)
2. Adding it after the last element of the current heap
3. Shifting it up into the correct position.
At the end of all the inputs you are to print out the first five elements of the heap array. Your heap
should be able to hold 100 integers. A pseudo‐code outline for the program is given below:
display a prompt for the file name
read in the file name
try to open the file
if the file fails to open
print an error message on the screen and exit
while we can read an int from the file
insert the int into the array
close the file
for i = 1 to 5
print the ith element of the heap
Do not implement the heap using a class or with STL. The heap must be implemented using a fixed
size array of ints (500 entries should be enough). The heap array and the index to the last item in the
heap should be global variables.
Information on the above functions is available from moodle and the week 2 lecture notes.
When you are finished, test your program using the provided text file named “Ex2.txt” and show
your code and the output to your lab tutor to receive your mark. Also, submit your file via unix
(banshee) using the submit command below.
$ submit -u login -c CSCI203 –a ex2 filename
where ‘login’ is your UNIX login ID and ‘filename’ is the name of your file.
If you are unable to attend your lab class and demonstrate your work on time due to circumstances
beyond your control (e.g. sickness), contact the coordinator (Ian or Koren) to request an extension.