tasks a-s

Task/Run-length-encoding/PowerShell/run-length-encoding.psh

@@ -0,0 +1,18 @@
+function Compress-RLE ($s) {
+    $re = [regex] '(.)\1*'
+    $ret = ""
+    foreach ($m in $re.Matches($s)) {
+        $ret += $m.Length
+        $ret += $m.Value[0]
+    }
+    return $ret
+}
+
+function Expand-RLE ($s) {
+    $re = [regex] '(\d+)(.)'
+    $ret = ""
+    foreach ($m in $re.Matches($s)) {
+        $ret += [string] $m.Groups[2] * [int] [string] $m.Groups[1]
+    }
+    return $ret
+}