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Playfair cipher: Difference between revisions

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Playfair cipher (view source)

Revision as of 14:11, 23 March 2022

24,134 bytes added ,  2 years ago
m
→‎{{header|Phix}}: syntax coloured, simplified by making keyword/option constants up-front
(→‎{{header|Tcl}}: fix method to build digrams)
m (→‎{{header|Phix}}: syntax coloured, simplified by making keyword/option constants up-front)
Line 2,079:
=={{header|Phix}}==
Originally translated from Kotlin, now uses a combined routine (playfair) for encoding and decoding, and direct char lookups, and x removal.
<!--<lang Phix>sequence table,(phixonline)-->
<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span>
findchar
<span style="color: #008080;">constant</span> <span style="color: #000000;">keyword</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"Playfair example"</span><span style="color: #0000FF;">,</span>
 
<span style="color: #000000;">option</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">'Q'</span> <span style="color: #000080;font-style:italic;">-- ignore Q
type pfoption(integer option)
-- option = 'J' -- replace J with I</span>
return find(option,"QJ")!=0
end type
 
pfoption pfo -- 'Q' or 'J'
<span style="color: #004080;">sequence</span> <span style="color: #000000;">table</span><span style="color: #0000FF;">,</span>
procedure build_table(string keyword, integer option)
<span style="color: #000000;">findchar</span>
-- option should be 'Q' to ignore Q, or 'J' to replace Js with I
pfo = option
<span style="color: #008080;">procedure</span> <span style="color: #000000;">build_table</span><span style="color: #0000FF;">()</span>
table = repeat(repeat(' ',5),5)
<span style="color: #000000;">table</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">5</span><span style="color: #0000FF;">),</span><span style="color: #000000;">5</span><span style="color: #0000FF;">)</span>
findchar = repeat(0,26)
<span style="color: #000000;">findchar</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">26</span><span style="color: #0000FF;">)</span>
findchar[pfo-'A'+1] = {0,0}
<span style="color: #000000;">findchar</span><span style="color: #0000FF;">[</span><span style="color: #000000;">option</span><span style="color: #0000FF;">-</span><span style="color: #008000;">'A'</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">}</span>
-- (note that any pfo (J/Q) in keyword are simply ignored)
<span style="color: #000080;font-style:italic;">-- (note any (J/Q) in keyword are simply ignored)</span>
string alphabet = upper(keyword) & "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
<span style="color: #004080;">string</span> <span style="color: #000000;">alphabet</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">upper</span><span style="color: #0000FF;">(</span><span style="color: #000000;">keyword</span><span style="color: #0000FF;">)</span> <span style="color: #0000FF;">&</span> <span style="color: #7060A8;">tagset</span><span style="color: #0000FF;">(</span><span style="color: #008000;">'Z'</span><span style="color: #0000FF;">,</span><span style="color: #008000;">'A'</span><span style="color: #0000FF;">)</span>
integer i=1, j=1
<span style="color: #004080;">integer</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span>
for k=1 to length(alphabet) do
<span style="color: #008080;">for</span> <span style="color: #000000;">k</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">alphabet</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
integer c = alphabet[k]
<span style="color: #004080;">integer</span> <span style="color: #000000;">c</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">alphabet</span><span style="color: #0000FF;">[</span><span style="color: #000000;">k</span><span style="color: #0000FF;">]</span>
if c>='A' and c<='Z' then
<span style="color: #008080;">if</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">>=</span><span style="color: #008000;">'A'</span> <span style="color: #008080;">and</span> <span style="color: #000000;">c</span><span style="color: #0000FF;"><=</span><span style="color: #008000;">'Z'</span> <span style="color: #008080;">then</span>
integer d = c-'A'+1
<span style="color: #004080;">integer</span> <span style="color: #000000;">d</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">-</span><span style="color: #008000;">'A'</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span>
if findchar[d]=0 then
<span style="color: #008080;">if</span> <span style="color: #000000;">findchar</span><span style="color: #0000FF;">[</span><span style="color: #000000;">d</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span>
table[i][j] = c
<span style="color: #000000;">table</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">][</span><span style="color: #000000;">j</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">c</span>
findchar[d] = {i,j}
<span style="color: #000000;">findchar</span><span style="color: #0000FF;">[</span><span style="color: #000000;">d</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">i</span><span style="color: #0000FF;">,</span><span style="color: #000000;">j</span><span style="color: #0000FF;">}</span>
j += 1
<span style="color: #000000;">j</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span>
if j=6 then
<span style="color: #008080;">if</span> <span style="color: #000000;">j</span><span style="color: #0000FF;">=</span><span style="color: #000000;">6</span> <span style="color: #008080;">then</span>
i += 1
if i<span style=6"color: then#000000;">i</span> exit<span endstyle="color: if#0000FF;">+=</span> --<span tablestyle="color: filled#000000;">1</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">6</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000080;font-style:italic;">-- table filled</span>
j = 1
<span style="color: #000000;">j</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
end for
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
end procedure
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
 
<span style="color: #000000;">build_table</span><span style="color: #0000FF;">()</span>
function clean_text(string plaintext)
-- get rid of any non-letters and insert X between duplicate letters
plaintext = upper(plaintext)
string cleantext = ""
integer prevChar = -1
for i=1 to length(plaintext) do
integer nextChar = plaintext[i]
if nextChar>='A' and nextChar<='Z'
and (nextChar!='Q' or pfo!='Q') then
if nextChar='J' and pfo='J' then nextChar = 'I' end if
if nextChar=prevChar then
cleantext &= 'X'
end if
cleantext &= nextChar
prevChar = nextChar
end if
end for
if remainder(length(cleantext),2) then
-- dangling letter at end so add another letter to complete digram
cleantext &= iff(cleantext[$]='X'?'Z':'X')
end if
return cleantext
end function
function remove_x(string text)
for i=2 to length(text)-1 do
if text[i]='X'
and ((text[i-1]=' ' and text[i-2]=text[i+1]) or
(text[i+1]=' ' and text[i-1]=text[i+2])) then
text[i] = '_'
end if
end for
return text
end function
 
function playfair(string text, integer step, sequence d)
string res = ""
for i=1 to length(text) by step do
integer {row1, col1} = findchar[text[i]-'A'+1],
{row2, col2} = findchar[text[i+1]-'A'+1]
if i>1 then res &= " " end if
if row1=row2 then
res &= table[row1][d[col1]] & table[row2][d[col2]]
elsif col1=col2 then
res &= table[d[row1]][col1] & table[d[row2]][col2]
else
res &= table[row1][col2] & table[row2][col1]
end if
end for
return res
end function
 
constant p1 = {2,3,4,5,1}, -- easier than playing with mod(+1,5)
m1 = {5,1,2,3,4} -- "" mod(-1,5)
function encode(string plaintext)
return playfair(clean_text(plaintext),2,p1)
end function
 
function decode(string ciphertext)
-- ciphertext includes spaces we need to skip, hence by 3
return remove_x(playfair(ciphertext,3,m1))
end function
<span style="color: #008080;">function</span> <span style="color: #000000;">clean_text</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">plaintext</span><span style="color: #0000FF;">)</span>
string keyword = "Playfair example"
<span style="color: #000080;font-style:italic;">--
build_table(keyword,'Q')
-- get rid of any non-letters and insert X between duplicate letters
printf(1,"Playfair keyword : %s\n",{keyword})
--</span>
printf(1,"Option: J=I or no Q (J/Q) : %s\n",pfo)
<span style="color: #000000;">plaintext</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">upper</span><span style="color: #0000FF;">(</span><span style="color: #000000;">plaintext</span><span style="color: #0000FF;">)</span>
printf(1,"The table to be used is :\n\n%s\n\n",{join(table,"\n")})
<span style="color: #004080;">string</span> <span style="color: #000000;">cleantext</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
string plaintext = "Hide the gold...in the TREESTUMP!!!!",
<span style="color: #004080;">integer</span> <span style="color: #000000;">prevChar</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">-</span><span style="color: #000000;">1</span>
encoded = encode(plaintext),
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">plaintext</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
decoded = decode(encoded)
<span style="color: #004080;">integer</span> <span style="color: #000000;">nextChar</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">plaintext</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
printf(1,"The plain text : %s\n\n",{plaintext})
<span style="color: #008080;">if</span> <span style="color: #000000;">nextChar</span><span style="color: #0000FF;">>=</span><span style="color: #008000;">'A'</span> <span style="color: #008080;">and</span> <span style="color: #000000;">nextChar</span><span style="color: #0000FF;"><=</span><span style="color: #008000;">'Z'</span>
printf(1,"Encoded text is : %s\n",{encoded})
<span style="color: #008080;">and</span> <span style="color: #0000FF;">(</span><span style="color: #000000;">nextChar</span><span style="color: #0000FF;">!=</span><span style="color: #008000;">'Q'</span> <span style="color: #008080;">or</span> <span style="color: #000000;">option</span><span style="color: #0000FF;">!=</span><span style="color: #008000;">'Q'</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span>
printf(1,"Decoded text is : %s\n",{decoded})</lang>
<span style="color: #008080;">if</span> <span style="color: #000000;">nextChar</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'J'</span> <span style="color: #008080;">and</span> <span style="color: #000000;">option</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'J'</span> <span style="color: #008080;">then</span> <span style="color: #000000;">nextChar</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">'I'</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">nextChar</span><span style="color: #0000FF;">=</span><span style="color: #000000;">prevChar</span> <span style="color: #008080;">then</span>
<span style="color: #000000;">cleantext</span> <span style="color: #0000FF;">&=</span> <span style="color: #008000;">'X'</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #000000;">cleantext</span> <span style="color: #0000FF;">&=</span> <span style="color: #000000;">nextChar</span>
<span style="color: #000000;">prevChar</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">nextChar</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">if</span> <span style="color: #7060A8;">odd</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cleantext</span><span style="color: #0000FF;">))</span> <span style="color: #008080;">then</span>
<span style="color: #000080;font-style:italic;">-- dangling letter at end so add another letter to complete diagram</span>
<span style="color: #000000;">cleantext</span> <span style="color: #0000FF;">&=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cleantext</span><span style="color: #0000FF;">[$]=</span><span style="color: #008000;">'X'</span><span style="color: #0000FF;">?</span><span style="color: #008000;">'Z'</span><span style="color: #0000FF;">:</span><span style="color: #008000;">'X'</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">cleantext</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">remove_x</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">text</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">text</span><span style="color: #0000FF;">)-</span><span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]=</span><span style="color: #008000;">'X'</span>
<span style="color: #008080;">and</span> <span style="color: #0000FF;">((</span><span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]=</span><span style="color: #008000;">' '</span> <span style="color: #008080;">and</span> <span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">2</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">])</span> <span style="color: #008080;">or</span>
<span style="color: #0000FF;">(</span><span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]=</span><span style="color: #008000;">' '</span> <span style="color: #008080;">and</span> <span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span><span style="color: #0000FF;">]))</span> <span style="color: #008080;">then</span>
<span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">'_'</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">text</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">playfair</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">text</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">step</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">sequence</span> <span style="color: #000000;">d</span><span style="color: #0000FF;">)</span>
<span style="color: #000080;font-style:italic;">--
-- text may be the plaintext or the encoded version
-- step is 2 for plaintext, 3 for encoded(/skip spaces)
-- d is {2,3,4,5,1} instead of mod(+1,5), or
-- {5,1,2,3,4} -- -1
--</span>
<span style="color: #004080;">string</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">text</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">by</span> <span style="color: #000000;">step</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">integer</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">row1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">col1</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">findchar</span><span style="color: #0000FF;">[</span><span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'A'</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">],</span>
<span style="color: #0000FF;">{</span><span style="color: #000000;">row2</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">col2</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">findchar</span><span style="color: #0000FF;">[</span><span style="color: #000000;">text</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]-</span><span style="color: #008000;">'A'</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">></span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">&=</span> <span style="color: #008000;">" "</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">row1</span><span style="color: #0000FF;">=</span><span style="color: #000000;">row2</span> <span style="color: #008080;">then</span>
<span style="color: #0000FF;">{</span><span style="color: #000000;">col1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">col2</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">d</span><span style="color: #0000FF;">[</span><span style="color: #000000;">col1</span><span style="color: #0000FF;">],</span><span style="color: #000000;">d</span><span style="color: #0000FF;">[</span><span style="color: #000000;">col2</span><span style="color: #0000FF;">]}</span>
<span style="color: #008080;">elsif</span> <span style="color: #000000;">col1</span><span style="color: #0000FF;">=</span><span style="color: #000000;">col2</span> <span style="color: #008080;">then</span>
<span style="color: #0000FF;">{</span><span style="color: #000000;">row1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">row2</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">d</span><span style="color: #0000FF;">[</span><span style="color: #000000;">row1</span><span style="color: #0000FF;">],</span><span style="color: #000000;">d</span><span style="color: #0000FF;">[</span><span style="color: #000000;">row2</span><span style="color: #0000FF;">]}</span>
<span style="color: #008080;">else</span>
<span style="color: #0000FF;">{</span><span style="color: #000000;">col1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">col2</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">col2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">col1</span><span style="color: #0000FF;">}</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #000000;">res</span> <span style="color: #0000FF;">&=</span> <span style="color: #000000;">table</span><span style="color: #0000FF;">[</span><span style="color: #000000;">row1</span><span style="color: #0000FF;">][</span><span style="color: #000000;">col1</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">&</span> <span style="color: #000000;">table</span><span style="color: #0000FF;">[</span><span style="color: #000000;">row2</span><span style="color: #0000FF;">][</span><span style="color: #000000;">col2</span><span style="color: #0000FF;">]</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">res</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">encode</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">plaintext</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">playfair</span><span style="color: #0000FF;">(</span><span style="color: #000000;">clean_text</span><span style="color: #0000FF;">(</span><span style="color: #000000;">plaintext</span><span style="color: #0000FF;">),</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3</span><span style="color: #0000FF;">,</span><span style="color: #000000;">4</span><span style="color: #0000FF;">,</span><span style="color: #000000;">5</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">})</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">decode</span><span style="color: #0000FF;">(</span><span style="color: #004080;">string</span> <span style="color: #000000;">ciphertext</span><span style="color: #0000FF;">)</span>
<span style="color: #000080;font-style:italic;">-- ciphertext includes spaces we need to skip, hence by 3</span>
<span style="color: #008080;">return</span> <span style="color: #000000;">remove_x</span><span style="color: #0000FF;">(</span><span style="color: #000000;">playfair</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ciphertext</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">5</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">3</span><span style="color: #0000FF;">,</span><span style="color: #000000;">4</span><span style="color: #0000FF;">}))</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Playfair keyword : %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">keyword</span><span style="color: #0000FF;">})</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Option: J=I or no Q (J/Q) : %s\n"</span><span style="color: #0000FF;">,</span><span style="color: #000000;">option</span><span style="color: #0000FF;">)</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"The table to be used is :\n\n%s\n\n"</span><span style="color: #0000FF;">,{</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #000000;">table</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">)})</span>
<span style="color: #004080;">string</span> <span style="color: #000000;">plaintext</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"Hide the gold...in the TREESTUMP!!!!"</span><span style="color: #0000FF;">,</span>
<span style="color: #000000;">encoded</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">encode</span><span style="color: #0000FF;">(</span><span style="color: #000000;">plaintext</span><span style="color: #0000FF;">),</span>
<span style="color: #000000;">decoded</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">decode</span><span style="color: #0000FF;">(</span><span style="color: #000000;">encoded</span><span style="color: #0000FF;">)</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"The plain text : %s\n\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">plaintext</span><span style="color: #0000FF;">})</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Encoded text is : %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">encoded</span><span style="color: #0000FF;">})</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"Decoded text is : %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">decoded</span><span style="color: #0000FF;">})</span>
<!--</lang>-->
{{out}}
<pre>
Line 2,207 ⟶ 2,211:
Decoded text is : HI DE TH EG OL DI NT HE TR E_ ES TU MP
</pre>
The only difference when option is 'J' is the 4<small><sup>th</sup></small> line of table is KNOQS
 
=={{header|Python}}==
Petelomax
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