Implemented return values

examples/hello/hello.q

@@ -1,19 +1,8 @@
-// Comment
 main() {
-	address := 4194304 + 1
-	length := (0 + 50 - 20) * 10 / 100
-
-	loop {
-		print(address, length)
-	}
+	x := f(2, 3)
+	syscall(60, x)
 }
 
-// Comment
-print(address, length) {
-	write(length-2, address, length)
-}
-
-// Comment
-write(fd, address, length) {
-	syscall(1, fd, address, length)
+f(x, y) {
+	return (x + y) * (x + y)
 }