Shooting in Circle

$100$ pirates stand in a circle, in positions numbered $1$ to $100$. Going around the circle, each living pirate in turn shoots the next living pirate: pirate $1$ shoots pirate $2$, pirate $3$ shoots pirate $4$, and so on. After pirate $99$ shoots pirate $100$, it is pirate $1$'s turn again, and this continues around the circle until only one pirate is left. Captain Jack Sparrow is one of the $100$. In which position should he stand to survive?