README.md

push_swap

This project was made in accordance with the project of School 21 (Ecole 42).

Preamble · Description · Installation and usage · Testing

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Preamble

The purpose of this project is to code algorithm for sorting list of integers using two stacks.

push_swap should sort in ascending order numbers into stack and display a sequence
of instructions that can sort given stack.

You can see the subject here: push_swap.

Main requirements, rules and code style: Norm.

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Description

Mandatory part

• At start of the programm there are two stacks named a and b.
  

• The stack a contains a random amount of integers which cannot be duplicated.
  

• The stack b is empty.

Allowed operations with stacks are:

1. sa : swap a - swap the first 2 elements at the top of stack a.
   Do nothing if there is only one or no elements.

2. sb : swap b - swap the first 2 elements at the top of stack b.
   Do nothing if there is only one or no elements.

3. ss : sa and sb at the same time.

4. 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.

5. 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.

6. ra : rotate a - shift up all elements of stack a by 1.
   The first element becomes the last one.

7. rb : rotate b - shift up all elements of stack b by 1.
   The first element becomes the last one.

8. rr : ra and rb at the same time.

9. rra : reverse rotate a - shift down all elements of stack a by 1.
   The last element becomes the first one.

10. rrb : reverse rotate b - shift down all elements of stack b by 1.
    The last element becomes the first one.

11. rrr : rra and rrb at the same time.

• At evaluation final grade depends on amount of instructions to sort the stack.

Bonus part

• In this section we should code a checker for push_swap.

• checker receives as arguments given stack a.
  It will then wait and read instructions on the standard input. If after executing those instructions, stack a is actually sorted
  and b is empty, then checker must display "OK\n" on the standard output.
  In every other case, checker must display "KO\n" on the standard output.

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Installation and usage

Makefile compiles given functions into push_swap or checker executable file.

Compiler: gcc

Flags: -Wall -Werror -Wextra

• Go to the project folder:

$ cd 'path_to_push_swap'

• Then typo one of these command:

Command	Description
make	compiling mandatory part
make bonus	compiling bonus part
make clean	clearing all .o files
make fclean	clearing all .o files and executables

• Example of executing push_swap :

./push_swap 3 5 2 7 9

• Example of executing checker with instructions received from push_swap :

ARG="3 5 2 7 9"; ./push_swap $ARG | ./checker $ARG

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Testing

• You can check code norm due to norminette.

• Following checkers should be executed in way like checker in this project:

  • Linux checker
  • MacOS checker

• push_swap_tester