(a ＋b) * c / d＋ e*(f＋g)
= ((a ＋b) * c / d)(e*(f＋g))+
= (((a ＋b) * c)d /)(e(f＋g)*)+
= ((a+b)c * d /)(e f g + *)+
= a b + c * d / e f g + * +

x=(a ＋b) * c / d＋ e*(f＋g)
(+,a,b,t1)
(+,f,g,t2)
(*,t1,c,t3)
(*,e,t2,t4)
(/,t3,d,t5)
(+,t4,t5,t6)
(=,t6,-,x)