A. P!=NP
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Count all pairs of integers $$$(n, p)$$$ such that $$$0 \le p \le P$$$, $$$p \neq n \cdot p$$$, and $$$p!=n \cdot p$$$.

Input

The input consists of a single integer $$$P$$$ ($$$1 \le P \le 10^5$$$) — the upper bound on $$$p$$$.

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Tests in subtasks are numbered from $$$1 - 10$$$ with samples skipped. Each test is worth $$$\frac{100}{10}=10$$$ points.

Tests $$$1 - 5$$$ will satisfy $$$P \le 1000$$$.

The remaining tests do not satisfy any additional constraints.

Output

Output a single integer — the number of integer values for $$$n$$$ and $$$p$$$ that satisfy the constraints.

Example
Input
4
Output
2
Note

In the sample test, the $$$2$$$ values of $$$(n,p)$$$ that work are $$$(2,3)$$$ and $$$(6,4)$$$.

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Problem Idea: willy108

Problem Preparation: xug

Occurrences: Novice A, Advanced A