Degree

The interpreter for the programming language Base_ABC can perform assignments of the form A := B * C (where A, B, and C are variable names), but it cannot directly compute exponentiation to a natural power. Therefore, computing an expression of the form A^N must be replaced by a sequence of multiplication commands.

For example, the command X := A^5 can be rewritten as the following sequence of three assignments, each involving one multiplication:

R_1 := A * A
R_2 := A * R_1
X := R_1 * R_2

Given $N$, determine the minimum number of assignment commands, each involving one multiplication, needed to compute A^N.