al possibl 3 lettered combination using a-z(only small characters),0-9,and -(hyphene)

[Joe_anna]

I just need a help for me to just generate all the possible combinations as a 3 lettered using a-z(only small characters),0-9,and -(hyphene) only.

the possible combinations can be aa9,a-9,s9h,7-g,etc..

Can any one help me with the possible code.

This combinations has to be generated once the application is loaded.