use proconio::input;

fn main(){
    input!{
        x: i64,
        y: i64,
        z: u64,
    }

    let mut ans: u64 = if x == 0 || y == 0{0} else{1};
    ans += (x.abs() as u64).div_ceil(z);
    ans += (y.abs() as u64).div_ceil(z);
    println!("{}", ans);
}