September 2017 Update

Task/Run-length-encoding/00META.yaml

@@ -1,2 +1,4 @@
 ---
+category:
+- Encodings
 note: Compression

Task/Run-length-encoding/Gambas/run-length-encoding.gambas

@@ -0,0 +1,23 @@
+Public Sub Main()
+Dim sString As String = "WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW"
+Dim siCount As Short = 1
+Dim siStart As Short = 1
+Dim sHold As New String[]
+Dim sTemp As String
+
+sString &= " "
+
+Repeat
+  sTemp = Mid(sString, siCount, 1)
+  Do
+    Inc siCount
+    If Mid(sString, siCount, 1) <> sTemp Then Break
+    If siCount = Len(sString) Then Break
+  Loop
+  sHold.add(Str(siCount - siStart) & sTemp)
+  siStart = siCount
+Until siCount = Len(sString)
+
+Print sString & gb.NewLine & sHold.Join(", ")
+
+End

Task/Run-length-encoding/Kotlin/run-length-encoding.kotlin

@@ -0,0 +1,14 @@
+tailrec fun runLengthEncoding(text:String,prev:String=""):String {
+    if (text.isEmpty()){
+        return prev
+    }
+    val initialChar = text.get(0)
+    val count = text.takeWhile{ it==initialChar }.count()
+    return runLengthEncoding(text.substring(count),prev + "$count$initialChar" )
+}
+
+fun main(args: Array<String>) {
+    assert(runLengthEncoding("TTESSST") == "2T1E3S1T")
+    assert(runLengthEncoding("WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW")
+                   == "12W1B12W3B24W1B14W")
+}

Task/Run-length-encoding/Sed/run-length-encoding-1.sed

@@ -0,0 +1,26 @@
+	/^$/ b
+:start
+	/^[0-9]/ b
+	s/^/1/
+:loop
+	h
+	/^9+([^0-9])\1+/ {
+		s/^(9+).*/0\1/
+		y/09/10/
+		G
+		s/^(.+)\n[0-9]+.(.*)/\1\2/
+		b loop }
+	/^[0-9]*[0-8]([^0-9])\1+/ {
+		s/^[0-9]*([0-8]).*/\1/
+		y/012345678/123456789/
+		G
+		s/^(.)\n([0-9]*)[0-8].(.*)/\2\1\3/
+		b loop }
+	/^[0-9]+9+([^0-9])\1+/ {
+		s/^[0-9]*([0-8]9+).*/\1/
+		y/0123456789/1234567890/
+		G
+		s/^(.+)\n([0-9]*)[0-8]9+.(.*)/\2\1\3/
+		b loop }
+	s/^([0-9]+.)(.*)/\2\1/
+	b start

Task/Run-length-encoding/Sed/run-length-encoding-2.sed

@@ -0,0 +1,21 @@
+	/^$/ b
+:start
+	/^[^0-9]/ b
+:loop
+	/^1[^0-9]/ {
+		s/^1(.)(\1*)(.*)/\3\1\2/
+		b start }
+	h
+	/^[0-9]*[1-9][^0-9]/ {
+		s/^[0-9]*([1-9]).*/\1/
+		y/123456789/012345678/
+		G
+		s/^([0-8])\n([0-9]*)[1-9]([^0-9])(.*)/\2\1\3\3\4/
+		b loop }
+	/^[0-9]+0[^0-9]/ {
+		s/^[0-9]*([1-9]0+)[^0-9].*/\1/
+		y/0123456789/9012345678/
+		G
+		s/^([0-9]+)\n([0-9]*)[1-9]0+([^0-9])(.*)/\2\1\3\3\4/
+		s/^0+//
+		b loop }

Task/Run-length-encoding/Sed/run-length-encoding-3.sed

@@ -0,0 +1,8 @@
+sed -rf encode.sed <<< "foo oops"
+# 1f2o1 2o1p1s
+
+sed -rf decode.sed <<< "1f2o1 2o1p1s"
+# foo oops
+
+(sed -rf decode.sed | sed -rf encode.sed) <<< 1000.
+# 1000.

Task/Run-length-encoding/Zkl/run-length-encoding-1.zkl

@@ -0,0 +1,18 @@
+const MAX_LEN=250, MIN_LEN=3;
+fcn compress(text){ // !empty byte/text stream -->Data (byte stream)
+   sink:=Data(); cnt:=Ref(0);
+   write:='wrap(c,n){ // helper function
+      while(n>MAX_LEN){
+         sink.write(1); sink.write(MAX_LEN); sink.write(c);
+	 n-=MAX_LEN;
+      }
+      if(n>MIN_LEN){ sink.write(1); sink.write(n); sink.write(c); }
+      else { do(n) { sink.write(c); } }
+   };
+   text.reduce('wrap(a,b){
+      if(a==b) cnt.inc();
+      else{ write(a,cnt.value); cnt.set(1); }
+      b
+   },text[0]) : write(_,cnt.value);
+   sink;
+}

Task/Run-length-encoding/Zkl/run-length-encoding-2.zkl

@@ -0,0 +1,6 @@
+fcn inflate(data){  //-->String
+   data.howza(3).pump(String,
+      fcn(c){ // if c==1, read n,c2 and expand, else write c
+         if(c=="\x01") return(Void.Read,2) else return(Void.Write,c) },
+      fcn(_,n,c){ c*n.toAsc() })
+}

Task/Run-length-encoding/Zkl/run-length-encoding-3.zkl

@@ -0,0 +1,5 @@
+text:="WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW";
+d:=compress(text);
+d.bytes().println();
+println(text.len()," bytes --> ",d.len()," bytes");
+println(text==inflate(d));