From dd0deaf15ce3a64b657cdced25a93dc1219ef3c6 Mon Sep 17 00:00:00 2001
From: Jason Orendorff <jason.orendorff@gmail.com>
Date: Wed, 21 Aug 2013 09:56:57 -0500
Subject: [PATCH] Fix amusing bug, discovered by my son J, that caused 1/(0-4)
 to be 1/-4 ("one negative-fourth") rather than -1/4.

---
 calculator-backends.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/calculator-backends.js b/calculator-backends.js
index 86395f4..d0b10f6 100644
--- a/calculator-backends.js
+++ b/calculator-backends.js
@@ -57,7 +57,7 @@ function gcd(a, b) {
 function Fraction(n, d) {
     if (d === undefined)
         d = new BigInteger(1);
-    var x = gcd(n, d);
+    var x = gcd(n.abs(), d);
     this.n = n.divide(x);
     this.d = d.divide(x);
 }