Problem Statement

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?

Input

Input is given from Standard Input in the following format:
N

Output

Print the answer.

Constraints

• N is an integer.
• $1 \leq N \leq 100$

Sample Input 1

5

Sample Output 1

3

By printing the 1-st, 2-nd pages on the 1-st sheet, 3-rd and 4-th pages on the 2-nd sheet, and 5-th page on the 3-rd sheet, we can print all the data on 3 sheets of paper.

Sample Input 2

2

Sample Output 2

1

Sample Input 3

100

Sample Output 3

50

见题面 Input 部分

见题面 Output 部分