load(x)&-ab(x)>[outl(x)];
shoot(x)&-ab(x)>[outl(x)=inl(x)&-inl(x)]&[outa(x)=-inl(x)&ina(x)];
load(A);
shoot(B);

outl(A)=inl(B);
ina(B)=ina(A);
ina(A);
outa(B);