Data commit

Task/Gray-code/BBC-BASIC/gray-code.basic

@@ -0,0 +1,15 @@
+      INSTALL @lib$+"STRINGLIB"
+
+      PRINT "   Decimal    Binary      Gray   Decoded"
+      FOR number% = 0 TO 31
+        gray% = FNgrayencode(number%)
+        PRINT number% "     " FN_tobase(number%, 2, 5) ;
+        PRINT "     " FN_tobase(gray%, 2, 5) FNgraydecode(gray%)
+      NEXT
+      END
+
+      DEF FNgrayencode(B%) = B% EOR (B% >>> 1)
+
+      DEF FNgraydecode(G%) : LOCAL B%
+      REPEAT B% EOR= G% : G% = G% >>> 1 : UNTIL G% = 0
+      = B%