Problem:
Score : 100 points

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?

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.

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

Solution in Rust (1.15.1) (judge verdict: Accepted)

#![allow(dead_code)]
#![allow(unused_variables)]
#![allow(unused_imports)]

use std::io::stdin;
use std::str::FromStr;
use std::cmp::min;
use std::process::exit;

fn read<T: FromStr>() -> T {
    let mut str = String::new();
    stdin().read_line(&mut str).ok();
    str.trim().parse().ok().unwrap()
}

fn read_vec<T: FromStr>() -> Vec<T> {
    let mut str = String::new();
    stdin().read_line(&mut str).ok();
    str.trim().split_whitespace().map(|e| e.parse().ok().unwrap()).collect()
}

fn read_n_vec<T: FromStr>(n: u64) -> Vec<Vec<T>> {
    let mut v_outer = Vec::new();
    for _ in 0..n {
        let v_inner = read_vec();
        v_outer.push(v_inner);
    }
    v_outer
}

fn main() {
    let n: u32 = read();
    println!("{}", (n + (2 - 1)) / 2);
}