1. function post(y^b)

2. foreach y in y^b

3. if i destination of C_i(y) is a parent

4. add y = C_i(y) to the bag ${\text{m}}_{\text{i}}{\text{.y}}_{\text{i}}^{\text{b}}$

5. else

6. add x = C_i(y) to the bag of ${\text{m}}_{\text{i}}{\text{.x}}_{\text{i}}^{\text{b}}$

7. end post