p02759 AtCoder Beginner Contest 157 - Duplex Printing
Takahashi wants to print a document with N pages double-sided, where two pages of data can be printed on one sheet of paper.

At least how many sheets of paper does he need?

Constraints

* N is an integer.
* 1 \leq N \leq 100

Input

Input is given from Standard Input in the following format:


N


Output

Print the answer.

Examples

Input

5


Output

3


Input

2


Output

1


Input

100


Output

50
```python
N = int(input())
print(str(N//2+N%2))
```