/* {{{ */ macro_rules! input { (source = $s:expr, $($r:tt)*) => { let mut iter = $s.split_whitespace(); input_inner!{iter, $($r)*} }; ($($r:tt)*) => { let s = { use std::io::Read; let mut s = String::new(); std::io::stdin().read_to_string(&mut s).unwrap(); s }; let mut iter = s.split_whitespace(); input_inner!{iter, $($r)*} }; } macro_rules! input_inner { ($iter:expr) => {}; ($iter:expr, ) => {}; ($iter:expr, $var:ident : $t:tt $($r:tt)*) => { let $var = read_value!($iter, $t); input_inner!{$iter $($r)*} }; } macro_rules! read_value { ($iter:expr, ( $($t:tt),* )) => { ( $(read_value!($iter, $t)),* ) }; ($iter:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($iter, $t)).collect::>() }; ($iter:expr, chars) => { read_value!($iter, String).chars().collect::>() }; ($iter:expr, usize1) => { read_value!($iter, usize) - 1 }; ($iter:expr, $t:ty) => { $iter.next().unwrap().parse::<$t>().expect("Parse error") }; } /* }}} */ pub fn ceil_div(a: i64, b: i64) -> i64 { (a + b - 1) / b } fn main() { input! { x: i64, y: i64, l: i64 } let h = ceil_div(x.abs(), l); let v = ceil_div(y.abs(), l); let mut res = h + v; res += if y >= 0 && x.abs() == 0 { 0 } else if y >= 0 && x.abs() > 0 { 1 } else if y < 0 { 2 } else { panic!() }; println!("{}", res); } /* vim:set foldmethod=marker: */