51% attack on New coins I have experienced 51% attack after launching a new altcoin last month. 

While i mined only 100 blocks using coin-cli generate 1, i noticed somebody already mined 2000 blocks within minutes attacking my network. I was running 2 nodes (without wallet) and 1 node (with wallet installed) in Ubuntu server.


Why would the attacker target new cryptocurrencies? Is he after coins? 
What changes in the code i have to implement to prevent the 51% attack?


My altcoin is based on scrypt (litecoin), Block generation time is 10 minutes/hour, Coin maturity 100 blocks, with parameters almost same as bitcoin.
Why would the attacker target new cryptocurrencies?


Why not? He has the same reasons as you to create blocks


  What changes in the code i have to implement to prevent the 51% attack?


Disable decentralization. Allow mining from one pubkey/address only :)