tasks a-s

Task/Range-expansion/JavaScript/range-expansion.js

@@ -0,0 +1,34 @@
+#!/usr/bin/env js
+
+function main() {
+    print(rangeExpand('-6,-3--1,3-5,7-11,14,15,17-20'));
+}
+
+function rangeExpand(rangeExpr) {
+
+    function getFactors(term) {
+        var matches = term.match(/(-?[0-9]+)-(-?[0-9]+)/);
+        if (!matches) return {first:Number(term)};
+        return {first:Number(matches[1]), last:Number(matches[2])};
+    }
+
+    function expandTerm(term) {
+        var factors = getFactors(term);
+        if (factors.length < 2) return [factors.first];
+        var range = [];
+        for (var n = factors.first; n <= factors.last;  n++) {
+            range.push(n);
+        }
+        return range;
+    }
+
+    var result = [];
+    var terms = rangeExpr.split(/,/);
+    for (var t in terms) {
+        result = result.concat(expandTerm(terms[t]));
+    }
+
+    return result;
+}
+
+main();