If player A
is invoking minimax then:
On Player A
's first turn of a run: maximise
On Player A
's second turn of a run: maximise again.
This relies of objective evaluations of the board being based from the perspective of A
. So regardless of whose turn it is on a state, objective(state)
is with reference to A
's gain from that state.
You will need a way to determine given a sate X
, was there a turn made in the parent state such that the current turn for player Z
is the second in a row. However you could also simply evaluate whose turn it is, and if it's A
's then perform maximisation as normal.