  The goal of this paper is the exact computation of the degrees
$\text{deg}(f^n)$ of the iterates of birational maps $f: \mathbb{P}^N
\dashrightarrow \mathbb{P}^N$. In the preceding companion paper, a new method
has been proposed based on the use of indices of polynomials associated to the
local blow-ups used to resolve contractions of hypersurfaces by $f$, and on the
control of the factorization of pull-backs of polynomials. This leads to
recurrence relations for the degrees and the indices. We apply this method to
several illustrative examples in three dimensions. These examples demonstrate
the flexibility of the method which, in particular, does not require the
construction of an algebraically stable lift of $f$, unlike the previously
known methods based on the Picard group.
