Move-to-front algorithm: Difference between revisions
Rename Perl 6 -> Raku, alphabetize, minor clean-up
Thundergnat (talk | contribs) (Rename Perl 6 -> Raku, alphabetize, minor clean-up) |
|||
Line 558:
hiphophiphop : [7 8 15 2 15 2 2 3 2 2 3 2 ]
Correct :)</pre>
=={{header|C sharp|C#}}==
<lang csharp>
using System;
using System.Collections.Generic;
using System.Text;
namespace MoveToFront
{
class Program
{
private static char[] symbolTable;
private static void setSymbolTable()
{
symbolTable = "abcdefghijklmnopqrstuvwxyz".ToCharArray();
}
private static void moveToFront(int charIndex)
{
char toFront = symbolTable[charIndex];
for (int j = charIndex; j > 0; j--)
{
symbolTable[j] = symbolTable[j - 1];
}
symbolTable[0] = toFront;
}
public static int[] Encode(string input)
{
setSymbolTable();
var output = new List<int>();
foreach (char c in input)
{
for (int i = 0; i < 26; i++)
{
if (symbolTable[i] == c)
{
output.Add(i);
moveToFront(i);
break;
}
}
}
return output.ToArray();
}
public static string Decode(int[] input)
{
setSymbolTable();
var output = new StringBuilder(input.Length);
foreach (int n in input)
{
output.Append(symbolTable[n]);
moveToFront(n);
}
return output.ToString();
}
static void Main(string[] args)
{
string[] testInputs = new string[] { "broood", "bananaaa", "hiphophiphop" };
int[] encoding;
foreach (string s in testInputs)
{
Console.WriteLine($"Encoding for '{s}':");
encoding = Encode(s);
foreach (int i in encoding)
{
Console.Write($"{i} ");
}
Console.WriteLine($"\nDecoding for '{s}':");
Console.WriteLine($"{Decode(encoding)}\n");
}
}
}
}
</lang>
=={{header|C++}}==
Line 650 ⟶ 727:
hiphophiphop -> encoded = 7 8 15 2 15 2 2 3 2 2 3 2 ; decoded = hiphophiphop
</pre>
=={{header|Clojure}}==
Line 1,122:
It's not clear, though, why anyone would think that this is any better than lookups against an unmodified symbol table.
=={{header|Java}}==
{{works with|Java|1.5+}}
Line 1,422 ⟶ 1,423:
edit
=={{header|M2000 Interpreter}}==
In Encode$() we use a string of parameters (function Quote$() make this)
Line 1,637 ⟶ 1,639:
correctly decoded to hiphophiphop
</pre>
=={{header|Phix}}==
Line 2,059 ⟶ 2,031:
"bananaaa" encodes to (1 1 13 1 1 1 0 0), which decodes "correctly" to "bananaaa".
"hiphophiphop" encodes to (7 8 15 2 15 2 2 3 2 2 3 2), which decodes "correctly" to "hiphophiphop".</pre>
=={{header|Raku}}==
(formerly Perl 6)
{{works with|rakudo|2015-09-24}}
<lang perl6>sub encode ( Str $word ) {
my @sym = 'a' .. 'z';
gather for $word.comb -> $c {
die "Symbol '$c' not found in @sym" if $c eq @sym.none;
@sym[0 .. take (@sym ... $c).end] .= rotate(-1);
}
}
sub decode ( @enc ) {
my @sym = 'a' .. 'z';
[~] gather for @enc -> $pos {
take @sym[$pos];
@sym[0..$pos] .= rotate(-1);
}
}
use Test;
plan 3;
for <broood bananaaa hiphophiphop> -> $word {
my $enc = encode($word);
my $dec = decode($enc);
is $word, $dec, "$word.fmt('%-12s') ($enc[])";
}</lang>
{{out}}
<pre>1..3
ok 1 - broood (1 17 15 0 0 5)
ok 2 - bananaaa (1 1 13 1 1 1 0 0)
ok 3 - hiphophiphop (7 8 15 2 15 2 2 3 2 2 3 2)</pre>
=={{header|REXX}}==
| |||