ICS 312 Spring 2025

Homework Assignment #5 [55 pts]

You are expected to do your own work on all homework assignments. You may (and are encouraged to) engage in general discussions with your classmates regarding the assignments, but specific details of a solution, including the solution itself, must always be your own work. (See the statement of Academic Dishonesty on the Syllabus.

How to turn in?

Assignments need to be turned in via Laulima. Check the Syllabus for the late assignment policy for the course.

What to turn in?

You must turn in a zip archive named ics312_hw5_xxx.zip, where “xxx” is your UH user name (e.g., for me, it would be ics312_hw5_henric.zip). The archive must contain a single top-level directory called ics312_hw5_xxx, where “xxx” is your UH user name (e.g., for me, it would be ics312_hw5_henric). In that directory you must have all the files named exactly as specified in the exercises below.

Expected contents of the ics312_hw5_xxx directory:

Deviation from the above specs will lead to lost points:

Overview

In this exercise we work towards implementing an in-the-terminal version of Wordle (TM). Your solution for Exercise #n is used as a starting point for exercise #n+1.

If you’ve never played Wordle, the goal is to discover a mystery word. The user enters guesses (that must be words). Letters that are correct and in the correct position are shown in green, and letters that are correct but not in the correct position are shown in yellow.

To implement Wordle we need to have the list of all 5-letter English words. This list is provided to you in file allwords.inc, which you should download and add to your source code. This file defines a .data segment that declares an integer 4-byte value at address num_words, and a byte sequence at address all_words. That sequence consists of [num_words] 5-letter words all glued together as whichtheretheiraboutwould….

You must include this file in your ics312_hw5_xxx directory and include it at the top of your source code as:

%include "allwords.inc"

Note that you can then define whatever .data segment as usual: a NASM source file can have multiple .data segment definitions.

Exercise #1: A Word Detector [20 pts]

Implement a program in source file hw5_ex1.asm that prompts the user for a 5-letter lower-case string, the guess, and prints “It’s a word!” or “It’s not a word!” based on whether the guess is a known 5-letter English word or not. You can assume that the user always enters correct input that is exactly 5 lower-case letters followed by a linefeed.

Here are example interactions with the program:

$ ./hw5_ex1
Enter a 5-letter guess: there
It's a word!

$ ./hw5_ex1
Enter a 5-letter guess: heavy
It's a word!

$ ./hw5_ex1
Enter a 5-letter guess: thinl
It's not a word!

$ ./hw5_ex1
Enter a 5-letter guess: xxasd
It's not a word!

          grep read_char hw5_ex1.asm | wc -l

Exercise #2: A Hangman-like Infinite Wordle [25 pts]

Implement a program in source file hw5_ex2.asm that first prompt the user for a positive integer. This integer is used to pick a mystery word to guess. The program computes the remainder of the division of this integer by [num_words], which gives the index of a word in the list of all words. For instance, if the user enters number 0, then the mystery word would be “which” (the first word in the list); if the user enters number 512451, then the mystery word would be “hands” (the 79-th word in the list).

The program then repeatedly asks the user for a 5-letter lower-case string, the guess. If the guess is not a word, then the program asks for a guess again. If the guess is a word, then the program prints, for each letter in the guess, an underscore if the letter is not a match or the upper-case version of the letter is the letter is a match.

For instance, if the mystery word is heavy, and the user enters ferry then the program will print _E__Y. This continues until the user has guessed the mystery word, and which point the program prints “You won!”. In other words, it’s like a Wordle that would only print the green letters but not the yellow letters.

Here are example interactions with the program:

$ ./hw5_ex2
Enter any integer: 9881
Enter a 5-letter guess: sages
                        SA___
Enter a 5-letter guess: xyzab
Enter a 5-letter guess: ljwrq
Enter a 5-letter guess: large
                        _ARGE
Enter a 5-letter guess: sarge
                        SARGE
You won!

$ ./hw5_ex2
Enter any integer: 958123
Enter a 5-letter guess: whatz
Enter a 5-letter guess: tires
                        _IRES
Enter a 5-letter guess: lires
Enter a 5-letter guess: bires
Enter a 5-letter guess: fires
                        _IRES
Enter a 5-letter guess: mires
                        _IRES
Enter a 5-letter guess: hires
                        HIRES
You won!

Exercise #3: A Hangman-like Finite Wordle [10 pts]

Implement a program in source file hw5_ex3.asm that operates just as the program in the previous exercise, but only allows the user to make 6 guesses. Only guesses that are English words count toward the number of used guesses (i.e., the user can enter an infinite number of non-word guesses). If the user has used all their guesses, then the program terminates and prints “You lost. The word was xxxxx” where “xxxxx” is the mystery word.

Here are example interactions with the program (the first one below is exactly the same behavior as that of the program in the previous question):

$ ./hw5_ex3
Enter any integer: 9881
Enter a 5-letter guess: sages
                        SA___
Enter a 5-letter guess: xyzab
Enter a 5-letter guess: ljwrq
Enter a 5-letter guess: large
                        _ARGE
Enter a 5-letter guess: sarge
                        SARGE
You won!

$ ./hw5_ex3
Enter any integer: 5076
Enter a 5-letter guess: which
                        _____
Enter a 5-letter guess: start
                        _____
Enter a 5-letter guess: runes
                        ___E_
Enter a 5-letter guess: sterq
Enter a 5-letter guess: xrrrr
Enter a 5-letter guess: nords
Enter a 5-letter guess: south
                        _____
Enter a 5-letter guess: helps
                        _____
Enter a 5-letter guess: gains
                        GA___
You lost. The word was: gamer

Exercise #4: A Full-Fledged Wordle [EXTRA CREDIT: 20 pts]

In source file hw5_ex4.asm implement a full-fledged Wordle that prints both the green and the yellow letters. Because we don’t do colors, the yellow letters are simply printed as lower-case letters. Here are example interactions with the program:

$ ./hw5_ex4
Enter any integer: 412351
Enter a 5-letter guess: stuff
                        _t___
Enter a 5-letter guess: whats
                        ___t_
Enter a 5-letter guess: taxes
                        T_X__
Enter a 5-letter guess: tonic
                        TOnI_
Enter a 5-letter guess: tobin
Enter a 5-letter guess: tofin
Enter a 5-letter guess: toxin
                        TOXIN
You won!

$ ./hw5_ex4
Enter any integer: 4429  
Enter a 5-letter guess: crane
                        _ra__
Enter a 5-letter guess: arias
                        Ar_a_
Enter a 5-letter guess: parry
                        _a_R_
Enter a 5-letter guess: snags
                        __ag_
Enter a 5-letter guess: ogres
                        oGr__
Enter a 5-letter guess: stool
                        __O__
You lost. The word was: agora

Hint: Implementing Wordle is not as easy as it seems, because a letter can occur multiple times in the mystery word and/or the user’s input. As simple approach operates as follows: