a-a a-b a-c aaa aab aac aad aae ab- aba abb abc abd abe ac- aca acb acc acd ace ad- ada adb adc add ade aea aeb aec aed aee baa bab bac bad bae bba bbb bbc bbd bbe bca bcb bcc bcd bce bda bdb bdc bdd bde be- bea beb bec bed bee c-- caa cab cac cad cae cba cbb cbc cbd cbe cca ccb ccc ccd cce cda cdb cdc cdd cde ce- cea ceb cec ced cee daa dab dac dad dae dba dbb dbc dbd dbe dca dcb dcc dcd dce dda ddb ddc ddd dde de- dea deb dec ded dee eaa eab eac ead eae eba ebb ebc ebd ebe ec- eca ecb ecc ecd ece ed- eda edb edc edd ede eea eeb eec eed eee