Ordered words: Difference between revisions
Added Forth
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<pre>abbott accent accept access accost almost bellow billow biopsy chilly choosy choppy effort floppy glossy knotty
</pre>
=={{header|Forth}}==
{{works with|4tH 3.61.2}}
This program uses a string stack, which means that all matching words are stored on a stack.
The longest word ends up on the top of the stack.
<lang Forth>
include lib/stmstack.4th \ include string stack library
: check-word ( a n -- a n f)
2dup bl >r \ start off with a space
begin
dup \ when not end of word
while
over c@ r@ >= \ check character
while
r> drop over c@ >r chop \ chop character off
repeat r> drop nip 0= \ cleanup and set flag
;
: open-file ( -- h)
1 dup argn = abort" Usage: ordered infile"
args input open error? abort" Cannot open file"
dup use \ return and use the handle
;
: read-file ( --)
0 >r \ begin with zero length
begin
refill \ EOF detected?
while
0 parse dup r@ >= \ equal or longer string length?
if \ check the word and adjust length
check-word if r> drop dup >r >s else 2drop then
else \ if it checks out, put on the stack
2drop \ otherwise drop the word
then
repeat r> drop \ clean it up
;
: read-back ( --)
s> dup >r type cr \ longest string is on top of stack
begin s> dup r@ >= while type cr repeat
2drop r> drop \ keep printing until shorter word
; \ has been found</lang>
Since the longest word is on top of the stack, the only thing to be done is to pop
all words from the stack until a shorter word is encountered. Consequently, all
words are listed in reverse order:
<pre>knotty
glossy
floppy
effort
choppy
choosy
chilly
biopsy
billow
bellow
almost
accost
access
accept
accent
abbott</pre>
=={{header|Fortran}}==
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