Score : 600 points
Given is a positive integer N.
We will choose an integer K between 2 and N (inclusive), then we will repeat the operation below until N becomes less than K.
In how many choices of K will N become 1 in the end?
Input is given from Standard Input in the following format:
N
Print the number of choices of K in which N becomes 1 in the end.
6
3
There are three choices of K in which N becomes 1 in the end: 2, 5, and 6.
In each of these choices, N will change as follows:
3141
13
314159265358
9