42 Push_Swap

Given a set of integers, sort it using a predefined set of instructions using two stacks. The instruction set is defined below. This program outputs a program in push_swap instructions that sorts the input integers.

Instruction set

For the following instructions, if the instruction is not possible, the part of it that can't be executed won't.

Code	Instruction	Action
sa	swap a	swaps the 2 top elements of stack a
sb	swap b	swaps the 2 top elements of stack b
ss	swap a + swap b	both sa and sb
pa	push a	moves the top element of stack b at the top of stack a
pb	push b	moves the top element of stack a at the top of stack b
ra	rotate a	shifts all elements of stack a from bottom to top
rb	rotate b	shifts all elements of stack b from bottom to top
rr	rotate a + rotate b	both ra and rb
rra	reverse rotate a	shifts all elements of stack a from top to bottom
rrb	reverse rotate b	shifts all elements of stack b from top to bottom
rrr	reverse rotate a + reverse rotate b	both rra and rrb

Algorithm

To update

Resources

Books

• Algorithms

Links

• Push Swap Tutorial