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m (→{{header|Phix}}: syntax coloured) |
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=={{header|Phix}}== |
=={{header|Phix}}== |
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Based on [[Run-length_encoding#Euphoria|Euphoria]], but uses a few string in place of sequence. |
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<lang Phix> |
<!--<lang Phix>(phixonline)--> |
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<span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span> |
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sequence out = {} |
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<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;">s</span><span style="color: #0000FF;">)</span> |
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integer prev_char,count = 1 |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span> |
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if length(s) then |
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<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> |
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prev_char = s[1] |
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<span style="color: #004080;">integer</span> <span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">],</span> |
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for i=2 to length(s) do |
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<span style="color: #000000;">count</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span> |
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if s[i]!=prev_char then |
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<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;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span> |
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out &= {count,prev_char} |
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<span style="color: #008080;">if</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]!=</span><span style="color: #000000;">ch</span> <span style="color: #008080;">then</span> |
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prev_char = s[i] |
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<span style="color: #000000;">r</span> <span style="color: #0000FF;">&=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">count</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">}</span> |
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count = 1 |
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<span style="color: #000000;">ch</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span> |
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else |
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<span style="color: #000000;">count</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span> |
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count += 1 |
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<span style="color: #008080;">else</span> |
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<span style="color: #000000;">count</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">1</span> |
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end for |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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out &= {count,prev_char} |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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end if |
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<span style="color: #000000;">r</span> <span style="color: #0000FF;">&=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">count</span><span style="color: #0000FF;">,</span><span style="color: #000000;">ch</span><span style="color: #0000FF;">}</span> |
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return out |
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<span style="color: #008080;">end</span> <span style="color: #008080;">if</span> |
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end function |
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<span style="color: #008080;">return</span> <span style="color: #000000;">r</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
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function decode(sequence s) |
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sequence out = {} |
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<span style="color: #008080;">function</span> <span style="color: #000000;">decode</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> |
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for i=1 to length(s) by 2 do |
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<span style="color: #004080;">string</span> <span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">""</span> |
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out &= repeat(s[i+1],s[i]) |
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<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;">s</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">by</span> <span style="color: #000000;">2</span> <span style="color: #008080;">do</span> |
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end for |
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<span style="color: #000000;">r</span> <span style="color: #0000FF;">&=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</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;">s</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">])</span> |
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return out |
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<span style="color: #008080;">end</span> <span style="color: #008080;">for</span> |
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end function |
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<span style="color: #008080;">return</span> <span style="color: #000000;">r</span> |
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<span style="color: #008080;">end</span> <span style="color: #008080;">function</span> |
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sequence s = encode("WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW") |
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pp(s) |
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<span style="color: #004080;">sequence</span> <span style="color: #000000;">s</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">encode</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW"</span><span style="color: #0000FF;">)</span> |
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?decode(s)</lang> |
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<span style="color: #0000FF;">?</span><span style="color: #000000;">s</span> |
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<span style="color: #0000FF;">?</span><span style="color: #000000;">decode</span><span style="color: #0000FF;">(</span><span style="color: #000000;">s</span><span style="color: #0000FF;">)</span> |
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<!--</lang>--> |
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{{out}} |
{{out}} |
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Note the character hints are desktop/Phix only and don't appear under p2js. |
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<pre> |
<pre> |
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{12,87'W',1,66'B',12,87'W',3,66'B',24,87'W',1,66'B',14,87'W'} |
{12,87'W',1,66'B',12,87'W',3,66'B',24,87'W',1,66'B',14,87'W'} |