has anyone ever tried to write a bitcoin miner in C or assembler using functional programming?

a hash-check should be based on simple arithmetic, cutting out all the corners might make it more efficient. optimizing the compiler for such operations should also be an option.

i don't know much about programming myself, but it puzzles me that its getting so hard to mine bitcoins when the amount of viable hashes drecases over time. cant just make the target range smaller?

kind regards,
Kat