finished Screen.

- a bit slow though

2 files changed, 38 insertions, 0 deletions

diff --git a/projects/12/MathTest/Math.jack b/projects/12/MathTest/Math.jack
index 6bac42e..01bce8f 100644
--- a/projects/12/MathTest/Math.jack
+++ b/projects/12/MathTest/Math.jack
@@ -28,6 +28,18 @@ class Math {
         return ~(x & twoToThe[i] = 0);

     }

 

+    function int sign(int x) {

+        if (x > 0) {

+            return 1;

+        } else {

+            if (x < 0) {

+                return -1;

+            } else {

+                return 0;

+            }

+        }

+    }

+

     /** Returns the absolute value of x. */

     function int abs(int x) {

         if (x > 0){

diff --git a/projects/12/MathTest/Math.vm b/projects/12/MathTest/Math.vm
index dad8ff5..513fc1a 100644
--- a/projects/12/MathTest/Math.vm
+++ b/projects/12/MathTest/Math.vm
@@ -44,6 +44,32 @@ push constant 0
 eq
 not
 return
+function Math.sign 0
+push argument 0
+push constant 0
+gt
+if-goto IF_TRUE0
+goto IF_FALSE0
+label IF_TRUE0
+push constant 1
+return
+goto IF_END0
+label IF_FALSE0
+push argument 0
+push constant 0
+lt
+if-goto IF_TRUE1
+goto IF_FALSE1
+label IF_TRUE1
+push constant 1
+neg
+return
+goto IF_END1
+label IF_FALSE1
+push constant 0
+return
+label IF_END1
+label IF_END0
 function Math.abs 0
 push argument 0
 push constant 0