Re: "Another thrice-damned version of Mastermind"

[jgallagher]

Very cool. My only question is why, in the for(@q){...}, do you have to set $a = $_? I tried to do it with just $_, and sure enough, it didn't work, but I have no idea why that is.

Spoilers below!

#!/usr/bin/perl -w

sub q { 
    $; = 1;                        # $; stores how many tries you've h
+ad; start at 1
    for (0..3) { 
        $;[$_] = int(rand(9))      # @; stores the correct four number
+s; set it up here
    }
} 

sub _ {
    print @_
}

&q;

for (;;) {
    $: = $~ = 0;        # set $: (right number in the right spot) and 
+$~ (right number) to 0
    _ "$/$; ";          # prints a newline then the number of tries yo
+u've had
    $_ = <>;            # read a line into $_
    
    if (/^\d{4}$/) {    # if the line is exactly 4 digits...
        @q = split //;  # @q holds the 4 digits
        
        --$#q;          # set $#q = 3, ignoring the newline at $q[4]
        $@ = -1;        # set $@ to -1
        
        # This loops through the input digits and checks for correctne
+ss
        
        for (@q) {                         # set $_ to each of the 4 i
+nput digits
            $a = $_;                       # set $a to the current dig
+it (why not leave it $_?)
            ($a == $;[++$@]) && ++$:       # increment $: if you have 
+a right number in the right spot
                || (grep /$a/, @;) && ++$~ # else increment $~ if you 
+have a right number in the wrong spot
        }
        
        _ "$~W$:B ";  # print out the total of right/wrong ($~W) and r
+ight/right ($:B)
        ++$;;         # increment number of tries
        
        $: == 4       # if we have four right numbers all in the right
+ spots
            | $; > 10 # or we have already had 10 tries
            && _ (@;) # print out the correct answer
            && &q     # and start the game over
    }
}

[Aristotle]

Taking a quick cursory look, I'd assume due to grep /$a/, @;

Makeshifts last the longest.

[tinypig]

Nice work. I was reviewing it and I honestly don't remember why I did that (it's been a while since I originally wrote it). The only thing I can think is that I might have been concerned about overwriting the digit. I did have a quit (q) command in there when it was longer, though that is just a shot in the dark. With your suggestion implemented, it does seem to work fine:

sub q{$;=1;for(0..3){$;[$_]=int(rand(9))}}sub _{print@_}&q;for(;;){$:=
+$~=0
;_"$/$; ";$_=<>;if(/^\d{4}$/){@q=split//;--$#q;$@=-1;for(@q){($_==$;[+
++$@]
)&&++$:||(grep/$_/,@;)&&++$~}_"$~W$:B ";++$;;$:==4|$;>10&&_(@;)&&&q}}

[jgallagher]

Actually, it doesn't. As per Aristotle's suggestion above, the (grep/$_/,@;) would return true every time, thus always telling you you had four correct numbers.

[tinypig]

Sorry, you guys are right. Strange, I thought I ran that this morning and it worked.