Lab 2: Scrabble
You are welcome to collaborate with one or two classmates on this lab, though it is expected that every student in any such group contribute equally to the lab.
GitHub now requires that you use SSH or a personal access token instead of a password to log in, but you can still use check50
and submit50
! See cs50.ly/github for instructions if you haven’t already!
Determine which of two Scrabble words is worth more.
$ ./scrabble
Player 1: COMPUTER
Player 2: science
Player 1 wins!
When to Do It
Background
In the game of Scrabble, players create words to score points, and the number of points is the sum of the point values of each letter in the word.
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | 3 | 3 | 2 | 1 | 4 | 2 | 4 | 1 | 8 | 5 | 1 | 3 | 1 | 1 | 3 | 10 | 1 | 1 | 1 | 1 | 4 | 4 | 8 | 4 | 10 |
For example, if we wanted to score the word Code
, we would note that in general Scrabble rules, the C
is worth 3
points, the o
is worth 1
point, the d
is worth 2
points, and the e
is worth 1
point. Summing these, we get that Code
is worth 3 + 1 + 2 + 1 = 7
points.
Getting Started
- Copy the “distribution code” (i.e., starter code) from cdn.cs50.net/2020/fall/labs/2/scrabble.c into a new file in your IDE called
scrabble.c
.- You can also download the distribution code by running the command
wget https://cdn.cs50.net/2020/fall/labs/2/scrabble.c
in CS50 IDE.
- You can also download the distribution code by running the command
Implementation Details
Complete the implementation of scrabble.c
, such that it determines the winner of a short scrabble-like game, where two players each enter their word, and the higher scoring player wins.
- Notice that we’ve stored the point values of each letter of the alphabet in an integer array named
POINTS
.- For example,
A
ora
is worth 1 point (represented byPOINTS[0]
),B
orb
is worth 3 points (represented byPOINTS[1]
), etc.
- For example,
- Notice that we’ve created a prototype for a helper function called
compute_score()
that takes a string as input and returns anint
. Whenever we would like to assign point values to a particular word, we can call this function. Note that this prototype is required for C to know thatcompute_score()
exists later in the program. - In
main()
, the program prompts the two players for their words using theget_string()
function. These values are stored inside variables namedword1
andword2
. - In
compute_score()
, your program should compute, using thePOINTS
array, and return the score for the string argument. Characters that are not letters should be given zero points, and uppercase and lowercase letters should be given the same point values.- For example,
!
is worth0
points whileA
anda
are both worth1
point. - Though Scrabble rules normally require that a word be in the dictionary, no need to check for that in this problem!
- For example,
- In
main()
, your program should print, depending on the players’ scores,Player 1 wins!
,Player 2 wins!
, orTie!
.
Walkthrough
Hints
-
You may find the functions
isupper()
andislower()
to be helpful to you. These functions take in a character as the argument and return a nonzero value if the character is uppercase (forisupper
) or lowercase (forislower
). -
To find the value at the
n
th index of an array calledarr
, we can writearr[n]
. We can apply this to strings as well, as strings are arrays of characters. -
Recall that computers represent characters using ASCII, a standard that represents each character as a number.
How to Test Your Code
Your program should behave per the examples below.
$ ./scrabble
Player 1: Question?
Player 2: Question!
Tie!
$ ./scrabble
Player 1: Oh,
Player 2: hai!
Player 2 wins!
$ ./scrabble
Player 1: COMPUTER
Player 2: science
Player 1 wins!
$ ./scrabble
Player 1: Scrabble
Player 2: wiNNeR
Player 1 wins!
Not sure how to solve?
Execute the below to evaluate the correctness of your code using check50
. But be sure to compile and test it yourself as well!
check50 cs50/labs/2021/x/scrabble
Execute the below to evaluate the style of your code using style50
.
style50 scrabble.c
How to Submit
Execute the below, logging in with your GitHub username and password when prompted. For security, you’ll see asterisks (*
) instead of the actual characters in your password.
submit50 cs50/labs/2021/x/scrabble