(unstack purple yellow robot)
(put-down purple robot)
(unstack yellow red robot)
(put-down yellow robot)
(unstack red orange robot)
(put-down red robot)
(pick-up purple robot)
(stack purple red robot)
(unstack orange blue robot)
(put-down orange robot)
(unstack blue green robot)
(put-down blue robot)
(pick-up green robot)
(stack green blue robot)
(pick-up orange robot)
(stack orange green robot)
(pick-up yellow robot)
(stack yellow orange robot)