Push_swap

This project is about sorting numbers considering two stacks and using only the following instructions:

• sa : swap a - swap the first 2 elements at the top of stack a . Do nothing if there is only one or no elements).
• sb : swap b - swap the first 2 elements at the top of stack b . Do nothing if there is only one or no elements).
• ss : sa and sb at the same time.
• pa : push a - take the first element at the top of b and put it at the top of a . Do nothing if b is empty.
• pb : push b - take the first element at the top of a and put it at the top of b . Do nothing if a is empty.
• ra : rotate a - shift up all elements of stack a by 1. The first element becomes the last one.
• rb : rotate b - shift up all elements of stack b by 1. The first element becomes the last one.
• rr : ra and rb at the same time.
• rra : reverse rotate a - shift down all elements of stack a by 1. The flast element becomes the first one.
• rrb : reverse rotate b - shift down all elements of stack b by 1. The flast element becomes the first one.
• rrr : rra and rrb at the same time

Getting Started

Usage

To generate the set of instructions for a set of numbers:

./push_swap n1 n2 n3...

and to check wether the set of instructions really sorts:

./push_swap n1 n2 n3... | ./checker [-v] n1 n2 n3 ...

Example

ARG=`ruby -e "puts (-50..50).to_a.shuffle.join(' ')"` ; ./push_swap $ARG | ./checker -v $ARG

Visualizer

The visualizer have several commands:

• Right arrow: do one step
• 0 (numpad): pause autoplay
• 1-9 (numpad): autoplay (1 is slowest, 9 is fastest)
• space: BOOSTER (play as fast as possible)

Prerequisites

You will need SDL2

Debian

sudo apt-get install sdl2

OSX

brew install sdl2

Compiling

make all

Author

• Youva Gaudé