___________00_____________________7_______________
________0000_____________________777______________
______0000______________________77777_____________
____00000______________________7777777____________
___00000______________________777777777___________
__000000____________77777777777777777777777777777
_0000000______________7777777777777777777777777___
_0000000_______________7777777777777777777777_____
_0000__00_________________77777777777777777_______
_0000__00000000__________777777777_777777777______
_000000000000___________7777777_______7777777_____
__0000000000___________77777_____________77777____
___0000_000000________777___________________777___
____00000_______0___________0000__________________
______000000__00000______000000___________________
________000000000000000000000_____________________
__________00000000000000000_______________________
______________000000000___________________________