fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let _n: usize = n.trim().parse().unwrap();
    let mut a = String::new();
    std::io::stdin().read_line(&mut a).ok();
    let mut a: Vec<isize> = a.trim().split_whitespace().map(|i| i.parse().unwrap()).collect();

    a.sort();
    let result: usize = a.iter().enumerate()
        .map(|pair| pair.0 as isize + 1 - pair.1)
        .map(|i| i.abs() as usize)
        .sum();
    println!("{}", result);
}