Mnemonics

Author: csvenja

Mnemonics.js

@@ -0,0 +1,50 @@
+/*
+
+Given a particular number say 637-8687 (NERVOUS) would be the word.
+So for the older keypad’s seen on telephone’s I would have to create Mnemonics.
+
+So for doing this, the first part being list out all the Permutations possible for a particular number series.
+
+Ex: listMnemonics(“723″) would result in
+PAD PBD PCD QAD QBD QCD RAD RBD RCD SAD SBD SCD
+PAE PBE PCE QAE QBE QCE RAE RBE RCE SAE SBE SCE
+PAF PBF PCF QAF QBF QCF RAF RBF RCF SAF SBF SCF
+
+*/
+
+var digitToAlpha = [
+    /* 0 */ "",
+    /* 1 */ "",
+    /* 2 */ "ABC",
+    /* 3 */ "DEF",
+    /* 4 */ "GHI",
+    /* 5 */ "JKL",
+    /* 6 */ "MNO",
+    /* 7 */ "PQRS",
+    /* 8 */ "TUV",
+    /* 9 */ "WXYZ"
+]
+
+function listMnemonics(number) {
+    var numberStr = number.toString(),
+        currentMnemonics = [],
+        nextMnemonics = [],
+        mnemonics = [];
+
+    if (numberStr.length === 0) {
+        return [""];
+    }
+
+    currentMnemonics = digitToAlpha[numberStr[0]].split("");
+    nextMnemonics = listMnemonics(numberStr.slice(1));
+
+    for (var i = 0, currentLen = currentMnemonics.length; i < currentLen; i++) {
+        for (var j = 0, nextLen = nextMnemonics.length; j < nextLen; j++) {
+            mnemonics.push(currentMnemonics[i] + nextMnemonics[j]);
+        }
+    }
+
+    return mnemonics;
+}
+
+console.log(listMnemonics(723));