Initial data commit

Task/Straddling-checkerboard/JavaScript/straddling-checkerboard.js

@@ -0,0 +1,41 @@
+<script>
+var alphabet=new Array("ESTONIA  R","BCDFGHJKLM","PQUVWXYZ./") // scramble alphabet as you wish
+var prefixes=new Array("",alphabet[0].indexOf(" "),alphabet[0].lastIndexOf(" "))
+
+function straddle(message){
+  var out=""
+  message=message.toUpperCase()
+  message=message.replace(/([0-9])/g,"/$1") // dumb way to escape numbers
+  for(var i=0;i<message.length;i++){
+    var chr=message[i]
+	if(chr==" ")continue
+	for(var j=0;j<3;j++){
+	  var k=alphabet[j].indexOf(chr)
+	  if(k<0)continue
+	  out+=prefixes[j].toString()+k
+	}
+	if(chr=="/")out+=message[++i]
+  }
+  return out
+}
+
+function unstraddle(message){
+  var out=""
+  var n,o
+  for(var i=0;i<message.length;i++){
+	n=message[i]*1
+    switch(n){
+	  case prefixes[1]: o=alphabet[1][message[++i]];break
+	  case prefixes[2]: o=alphabet[2][message[++i]];break
+	  default: o=alphabet[0][n]
+	}
+	o=="/"?out+=message[++i]:out+=o
+  }
+  return out
+}
+
+str="One night-it was on the twentieth of March, 1888-I was returning."
+document.writeln(str)
+document.writeln(straddle(str))
+document.writeln(unstraddle(straddle(str)))
+</script>