Two Eggs, One Hundred Floors

A building has 100 floors. There is a critical floor f such that an egg dropped from floor f or above breaks, and an egg dropped from any floor below f survives (f may be any of 1..100, or eggs never break, treated as f = 101). You have exactly 2 identical eggs; a broken egg cannot be reused, but an egg that survives a drop can be dropped again. What is the minimum number of drops that GUARANTEES determining f in the worst case? (Drops may be chosen adaptively.)