If you mine the block you get 25btc on your address, this is the simple and fastest way to check it since most people have less on their wallet
No, it's not the simple and fastest way to check. All your program does is check whether or not an address has a balance of more than 20 coins. Your program will fail at the next block halving since the reward will only be 12.5
BTC.
If you're going to implement something, do it right. Kano has explained exactly how to do it.