return [[ 0, 0, 0, 0 ],
[ 0, 4, 0, 0 ],
[ 0, 8, 0, 0 ],
[ 5, 0, 0, 0 ],
[ 5, 4, 0, 0 ],
[ 5, 8, 0, 0 ],
[ 10, 0, 0, 0 ],
[ 10, 4, 0, 0 ],
[ 10, 8, 0, 0 ],
[ 15, 0, 0, 0 ],
[ 15, 4, 0, 0 ],
[ 15, 8, 0, 0 ]];;