Largest prime factor

Everybody knows any number can be combined by the prime number.
Now, your task is telling me what position of the largest prime factor.
The position of prime 2 is 1, prime 3 is 2, and prime 5 is 3, etc.
Specially, LPF(1) = 0.

Each line will contain one integer n(0 < n < 1000000).

Output the LPF(n).

1
2
3
4
5

0
1
2
1
3

Wiskey

HDU 2007-11 Programming Contest_WarmUp

威士忌