Implement Benders'

min,$-x_1-2x_2-3x_3-x_4,$

$s.t.x_1+x_2+2x_3+x_4,12$

$,-x_1+x_2,4$

$,2x_1+x_2,x_3+x_4,6$

$,8$

$,x_1,x_2,x_3,x_4,0$

Clearly state the master and subproblems, and the new constraint to be added at the end of the iteration.