Just another update

Task/Gray-code/R/gray-code.r

@@ -0,0 +1,25 @@
+GrayEncode <- function(binary) {
+	gray <- substr(binary,1,1)
+	repeat {
+	if  (substr(binary,1,1) != substr(binary,2,2)) gray <- paste(gray,"1",sep="")
+	else gray <- paste(gray,"0",sep="")
+	binary <- substr(binary,2,nchar(binary))
+	if (nchar(binary) <=1) {
+		break
+		}
+	}
+return (gray)
+}
+GrayDecode <- function(gray) {
+	binary <- substr(gray,1,1)
+	repeat {
+	if  (substr(binary,nchar(binary),nchar(binary)) != substr(gray,2,2)) binary <- paste(binary ,"1",sep="")
+	else binary <- paste(binary ,"0",sep="")
+	gray <- substr(gray,2,nchar(gray))
+
+	if (nchar(gray) <=1) {
+		break
+		}
+	}
+return (binary)
+}