I am building an exchange where you can buy and sell tokens.

I have a contract `Exchange`. It contains a function `sellTokens` which will take the amount of tokens entered by a user and give them a corresponding amount of ether.

However, when the contract is initiated, it will always have a balance of 0 ether until `buyTokens` function is executed and the contract is funded with some ethereum.

Question: What is the best way to fund this contract on creation? Does this have to be done manually after the contract has been deployed or is it possible to automate this in the constructor?

Please let me know if I can provide any more information.