Bsr main
	HALT
main:
	LINK 0
	AJS 2
	LDC 10
	AJS -3
	Bsr fac
	LDR R3
	TRAP 0
	AJS 1
	AJS -1
	UNLINK
	RET
fac:
	LINK 1
	LDL 1
	LDC 1
	EQ
	BRF 8
	LDC 1
	STR R3
	UNLINK
	RET
	BRA 20
	LDL 1
	AJS 2
	LDL 1
	LDC 1
	SUB
	AJS -3
	Bsr fac
	LDR R3
	MUL
	STR R3
	UNLINK
	RET
	UNLINK
	RET