There are seats numbered 1 to 100.

There are people numbered 1 to 100.

They take the seats in the order of their number. A person numbered 'i' is assigned seat number 'i'.

Person #1 is drunk - so he takes any seat at random.

Rest everyone takes his/her seat, if empty else picks a random seat from the available free seats.

Q: What is probability that person#100 sits on his assigned seat?

I haven't been able to make much progress here. Any hints plz?