(phixonline)-->
with javascript_semantics
function compress(string uncompressed)
integer dict = new_dict()
sequence result = {}
integer dictSize = 255, c
string word = ""
for i=0 to 255 do
setd(""&i,i,dict)
end for
for i=1 to length(uncompressed) do
c = uncompressed[i]
if getd_index(word&c,dict) then
word &= c
else
result &= getd(word,dict)
dictSize += 1
setd(word&c,dictSize,dict)
word = ""&c
end if
end for
if word!="" then
result &= getd(word,dict)
end if
destroy_dict(dict)
return result
end function
function decompress(sequence compressed)
integer dict = new_dict()
integer dictSize = 255, k, ki
string dent = "", result = "", word = ""
for i=0 to 255 do
setd(i,""&i,dict)
end for
for i=1 to length(compressed) do
k = compressed[i]
ki = getd_index(k,dict)
if ki then
dent = getd_by_index(ki,dict)
elsif k=dictSize then
dent = word&word[1]
else
return {NULL,i}
end if
result &= dent
setd(dictSize,word&dent[1],dict)
dictSize += 1
word = dent
end for
destroy_dict(dict)
return result
end function
constant example = "TOBEORNOTTOBEORTOBEORNOT"
sequence com = compress(example)
pp(com,{pp_IntCh,true,pp_Maxlen,90})
?decompress(com)