a-a a-c aaa aac aad aae aax ac- aca acc acd ace acx ad- ada adc add ade adx aea aec aed aee aex ax- axa axe axx c-- caa cac cad cae cax cca ccc ccd cce ccx cda cdc cdd cde cdx ce- cea cec ced cee cex cxc cxx daa dac dad dae dax dca dcc dcd dce dcx dda ddc ddd dde ddx de- dea dec ded dee dex dxc dxd dxx eaa eac ead eae eax ec- eca ecc ecd ece ecx ed- eda edc edd ede edx eea eec eed eee eex ex- exa exc exd exe exx xaa xac xad xcd xcx xda xdc xde xed xee xex xxx