digraph parser_FSM_diagram {
	graph [
		label="parser FSM diagram"
		labelloc="t"
		fontname="Helvetica,Arial,sans-serif"
        rankdir=BT
	]
	node [
		fontname="Helvetica,Arial,sans-serif"
		// shape=record
		style=filled
		fillcolor=gray95
        
	]
    edge [
        
    ]
    NUM //[label=<{ NUM } | { 1 - 9 } >]
    START -> NUM
    NUM -> NUM
    NUM -> DOT
    DOT -> NUM

    Operator //[label=<{ Operator } | { ! $ + - / * ( ) ^ % = }>]
    NUM -> Operator
    Operator -> NUM
    Operator -> Label
    Operator -> END
    START -> Label
    START -> END
    Label -> Operator
    Label -> END
    NUM -> END
}