/a-cpp-university-assignment-in-c

A C++ university assignment solved in C

Primary LanguageC

A C++ University Assignment in C

A C++ university assignment, paraphrased by The Cherno in the video I did a C++ University Assignment, and (hopefully) solved by me in C.

Why? It's healthy to write something in C once in a while, but I don't do it very often. It's a bit like jogging in that respect. Today just happened to be the day I felt like going jogging I guess.

The assignment

  • Marked automatically

  • "Failure to follow this guideline will result in 0."

  • Exactly one file: main.cpp [or in my case, main.c]

  • No design

  • Implement a very specific hash table

  • Keys are lower-case English words (eg. apple)

  • Length of a key is at most 10

  • Hash function = "simply using the last character" (eg. hash of apple is 'e')

  • Hash table contains exactly 26 slots (a-z), you won't need more

  • Table slots have three different statuses: "never used", "tombstone", "occupied"

  • Table starts with never used

  • Searching works as follows:

    • Given a key, take its last character as the hash value
    • First try the corresponding table slot
    • If the key is there, you've found it, if it's "never used", it doesn't exist
    • If the key is "occupied" or "tombstone", then move to next slot (may need to wrap the table)
    • Keep trying until key is found, or we're certain it doesn't exist

  • Insertion works as follows:

    • First perform search to see if key exists - if it does, do nothing
    • Take the last character of key as hash value
    • If that slot is not occupied ("never used" or "tombstone"), put the key there and occupy the slot
    • If it's occupied, try the next slot until you find a free slot

  • Deletion works as follows:

    • Given a key, search for it to locate its slot (if it doesn't exist do nothing)
    • If found, change to "tombstone"

  • When program starts init empty hash table (26 "never used" slots)

  • Command line input is 1-26 "modification moves" separated by spaces, moves are:

    • AWord - (character A followed by a lower-case English word of up to 10 characters)
      • eg. Aapple means insert key "apple" into hash table
    • DWord - (character D followed by word as above)
      • eg. Dapple means delete key "apple" from hash table

  • Once input is processed, output is all the slots in the hash table that have "occupied" values, separated by spaces

  • Ignore invalid inputs

    Sample input: Aapple Aorange Dapple Astrawberry

    Sample output: orange strawberry

  • Submit via SVN

  • Marking done automatically - total mark is 10

    • 1 mark for compiling
    • 9 marks for 9 test cases (1 per successful test case)

  • Code compiled using g++ -o main.out -std=c++11 -O2 -Wall main.cpp