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SPEAKER 1: Let's take a look at how you
might have solved the Scrabble problem.

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Recall that in this
problem your task was

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to write a program in C that
could take two different words

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and figure out which one of
them would have been worth

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more points in a game of Scrabble.

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Let's see how you might have done that.

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We gave you some distribution
code in scrabble.c already.

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But the place you
probably wanted to start

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was by writing this
compute score function.

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This function that
accepted a word as input

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and could tell you how many
points that word was worth.

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So let's scroll down to
the compute score function.

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Ultimately, in order to figure out
how many points the word is worth,

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we want to go through each
of the characters one by one

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and figure out how much
each character is worth,

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adding up all of those results.

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As we add up all of
those results, it's going

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to be helpful to have some variable
that's keeping track of the score

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so far.

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And so that's the first thing that we
do inside this compute score function.

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We have an integer called
score equal to zero.

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And that variable is going to keep
track of the score for the current word.

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Now what we need to do is
loop over the entire word,

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looking at each character one at a time.

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To do so, we have a for loop,
where we start with int i equals 0.

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i is going to represent
the index of the character.

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And in order to complete this loop, we
need to know how long the string is.

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So to do that, we can
use the strlen function

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to access the length of the string,
storing that inside of a variable

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called len.

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We're going to repeat this loop
as long as i is less than len,

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increasing i by one every time
this loop completes an iteration.

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Ultimately, this is going
to have i start at zero,

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the first character in the
string, then become 1, 2, 3,

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and so forth all the way until
we get to the end of the string.

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Now there are two cases
we need to consider here.

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This character might be an
uppercase letter, in which case

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it's worth points, or it might be
a lowercase letter, in which case

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it's also going to be worth
some number of points.

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And for any other type of character,
like a digit, or a punctuation,

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or a space, those are not going
to be worth any points at all.

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So let's first deal with
the uppercase situation.

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We can use the isupper function to
check if any particular character is

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an uppercase letter.

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And so we can check for word
square bracket i, meaning,

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take that string "word"
and access character

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i for whatever i happens to be
for this iteration of the loop.

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If this current character, word
bracket i is an uppercase letter,

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well then we need to update the score.

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How will we know how
to update the score?

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Well ultimately, we're going to use that
points array at the top of our file.

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This array gives us the
point value for each letter

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of the alphabet, where points
square brackets 0 represents

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the score for the letter A.
Points square bracket 1 represents

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the score for the letter B, and so on.

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But if you recall from our ASCII
relationship between characters

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and what numbers represent
those characters,

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capital letter A is not actually
represented by the number 0.

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It's represented by the number 65.

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And the capital letter B is
represented by the number 66.

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And capital C by 67.

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So we need to somehow translate those
ASCII values 65, 66, 67 for A, B, and C

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into 0, 1, and 2, which
will be the indexes we

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want to use into this points array.

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How do we do that?

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Well, ultimately, every letter's
ASCII value for the uppercase letters

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is 65 more than whatever
index value we actually want

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to use inside of this points array.

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So in order to translate that
character into its corresponding index,

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I could say, words square
bracket i minus 65,

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where capital A, which is
65 minus 65 would give us 0.

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So ultimately, we're accessing
POINTS square brackets

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0 to get access to the number of points
that corresponds to capital letter A.

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For capital letter B, it
would have been 66 minus 65.

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And that would give us
POINTS square bracket

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1 for accessing the number of
points we would get for a capital B.

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But since 65 is really the same thing
as capital A in terms of how they're

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represented, it's a little
bit cleaner in my code

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to just say word i minus
capital A. That way

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I don't need to know
that 65 just so happens

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to correspond to the capital letter A.

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So ultimately what I'm
doing here is saying word

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square bracket i minus capital A. That
is going to give me an index value.

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If word square bracket i is capital A,
then it's capital A minus capital A.

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That's zero.

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If word square bracket
i is capital Z, then I'm

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going to get capital Z minus
capital A, which is going to be 25.

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Those values correspond to
an index in the points array.

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So by putting that in square
brackets inside of POINTS,

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I can access how many points
that particular character

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is going to be worth.

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Whatever number of points
that character is worth,

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I'm going to then add that to the score.

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And that's going to update the value
of score in response to this character.

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Then I need to do the same
thing for lower case letters.

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If islower, this particular character,
we're going to do the same logic,

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adding to the score as well.

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But this time, subtracting lowercase
A, 97, instead of uppercase A, 65.

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To make sure that we're able to get
the correct index inside of that points

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array.

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This condition has an if and an else if.

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We don't need an else condition.

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The else case would handle characters
that are not letters at all.

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Numbers or punctuation, for example.

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But in those cases, since we
don't need to do anything,

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the score is not going to change, we
can just leave that case off entirely.

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We only consider uppercase
and lowercase letters.

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And at the very end, once we
have our final value for score,

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we can return the value of score.

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What is our main function that I
need to do with that information?

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Well, we need to print the winner.

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So we can compare those scores.

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If score1 is greater than
score2, we print "Player 1 wins!"

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Otherwise, if score1 is less than
score2, we print "Player 2 wins!"

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And else, the only other
possibility is that both players

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have the same score, in which
case our program is going

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to print that there has been a tie.

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Once you compile and run that program,
you should be able to type in two words

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and see which one of them would win in
a game of Scrabble My name is Brian.

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And this was Scrabble.

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