Positive integer n is given. How many tuples (A,B,C) of positive integers satisfy A⋅B+C=n?
One positive integer n (2≤n≤108).
Print the required number of tuples.
For n=3 there are exactly three triplets:
(1,1,2), since 1⋅1+2=3;
(1,2,1), since 1⋅2+1=3;
(2,1,1), since 2⋅1+1=3.