f1 = x1
f2 = ( ( ( x14*x1) *( ~x15) ) +( ( x2*( x14+x1) ) *( ~x15) ) )
f3 = x2
f4 = ( ( x16+x17) *( ~x1) )
f5 = x4
f6 = ( x5*( ~x15) )
f7 = x6
f8 = ( ( ( x13*( ( x11+x20) +x21) ) *( ~x4) ) *( ~( ( ( x13*( ~x11) ) *( ~x20) ) *( ~x21) ) ) )
f9 = ( x8+( ( x9*( ~x18) ) *( ~x19) ) )
f10 = ( ( x8+( ( x9*( ~x18) ) *( ~x19) ) ) *( x20+x21) )
f11 = ( ( ( ~( x8+( ( x9*( ~x18) ) *( ~x19) ) ) ) +x20) +x21)
f12 = ( ~x5)
f13 = x12
f14 = ( x13*( ( x11+x20) +x21) )
f15 = ( ( ( x13*( ~x11) ) *( ~x20) ) *( ~x21) )
f16 = x16
f17 = x17
f18 = x18
f19 = x19
f20 = x20
f21 = x21