#[allow(unused_imports)] use std::cmp::*; #[allow(unused_imports)] use std::collections::*; use std::io::{Write, BufWriter}; // https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 macro_rules! input { ($($r:tt)*) => { let stdin = std::io::stdin(); let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock())); let mut next = move || -> String{ bytes .by_ref() .map(|r|r.unwrap() as char) .skip_while(|c|c.is_whitespace()) .take_while(|c|!c.is_whitespace()) .collect() }; input_inner!{next, $($r)*} }; } macro_rules! input_inner { ($next:expr) => {}; ($next:expr, ) => {}; ($next:expr, $var:ident : $t:tt $($r:tt)*) => { let $var = read_value!($next, $t); input_inner!{$next $($r)*} }; } macro_rules! read_value { ($next:expr, [graph1; $len:expr]) => {{ let mut g = vec![vec![]; $len]; let ab = read_value!($next, [(usize1, usize1)]); for (a, b) in ab { g[a].push(b); g[b].push(a); } g }}; ($next:expr, ( $($t:tt),* )) => { ( $(read_value!($next, $t)),* ) }; ($next:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($next, $t)).collect::>() }; ($next:expr, chars) => { read_value!($next, String).chars().collect::>() }; ($next:expr, usize1) => (read_value!($next, usize) - 1); ($next:expr, [ $t:tt ]) => {{ let len = read_value!($next, usize); read_value!($next, [$t; len]) }}; ($next:expr, $t:ty) => ($next().parse::<$t>().expect("Parse error")); } #[allow(unused)] macro_rules! debug { ($($format:tt)*) => (write!(std::io::stderr(), $($format)*).unwrap()); } #[allow(unused)] macro_rules! debugln { ($($format:tt)*) => (writeln!(std::io::stderr(), $($format)*).unwrap()); } // ref: https://kuretchi.github.io/blog/entries/automaton-dp/ /// An (almost) DFA. trans is allowed to return None. /// S: alphabet (the set consisting of letters) trait DFA { fn size(&self) -> usize; fn trans(&self, state: usize, char: S) -> Option; fn init(&self) -> Vec; fn is_final_state(&self, state: usize) -> bool; } struct Prod(A, B); impl, B: DFA> DFA for Prod { fn size(&self) -> usize { self.0.size() * self.1.size() } fn trans(&self, state: usize, char: S) -> Option { let w = self.1.size(); let (x, y) = (state / w, state % w); if let Some(to1) = self.0.trans(x, char) { if let Some(to2) = self.1.trans(y, char) { return Some(to1 * w + to2); } } None } fn init(&self) -> Vec { let w = self.1.size(); let b_init = self.1.init(); let mut ans = vec![]; for av in self.0.init() { for &bv in &b_init { ans.push(av * w + bv); } } ans } fn is_final_state(&self, state: usize) -> bool { let w = self.1.size(); let (x, y) = (state / w, state % w); self.0.is_final_state(x) && self.1.is_final_state(y) } } trait ActionMonoid { type T; fn add(&self, x: Self::T, y: Self::T) -> Self::T; fn act(&self, x: Self::T, letter: S) -> Self::T; fn zero(&self) -> Self::T; fn one(&self) -> Self::T; } struct Add; impl ActionMonoid for Add { type T = i64; fn add(&self, x: i64, y: i64) -> i64 { x + y } fn act(&self, x: i64, _y: S) -> i64 { x } fn zero(&self) -> i64 { 0 } fn one(&self) -> i64 { 1 } } /// Digital DP. /// Finds \sum_{s < a, s in final} f(s), \sum_{s = a, s in final} f(s). /// Verified by: yukicoder No.1106 /// https://yukicoder.me/submissions/510954 fn digital_dp, M: ActionMonoid>( dfa: A, monoid: M, alpha: &[S], a: &[S] ) -> [M::T; 2] where M::T: Copy { let n = dfa.size(); let len = a.len(); let init = dfa.init(); let mut dp = vec![vec![[monoid.zero(); 2]; n]; len + 1]; for &v in &init { dp[0][v][1] = monoid.one(); } for i in 0..len { for j in 0..n { for eq in 0..2 { let val = dp[i][j][eq]; for &c in alpha { if eq == 1 && c > a[i] { continue; } if let Some(to) = dfa.trans(j, c) { let toeq = eq & if c == a[i] { 1 } else { 0 }; dp[i + 1][to][toeq] = monoid.add(dp[i + 1][to][toeq], monoid.act(val, c)); } } } } } let mut ans = [monoid.zero(); 2]; for i in 0..n { if dfa.is_final_state(i) { for j in 0..2 { ans[j] = monoid.add(ans[j], dp[len][i][j]); } } } ans } struct A; impl DFA for A { fn size(&self) -> usize { 1 } fn trans(&self, _state: usize, char: i64) -> Option { if char % 3 == 0 { Some(0) } else { None } } fn init(&self) -> Vec { vec![0] } fn is_final_state(&self, _state: usize) -> bool { true } } fn solve() { let out = std::io::stdout(); let mut out = BufWriter::new(out.lock()); macro_rules! puts { ($($format:tt)*) => (let _ = write!(out,$($format)*);); } input! { n: i64, } let div = max(min(n, 100), 10); let mut tot = (div - 9) / 3; if div >= 100 { let mut dig = vec![]; let mut v = n; while v > 0 { dig.push(v % 10); v /= 10; } dig.reverse(); let alpha: Vec<_> = (0..10).collect(); let ans = digital_dp(A, Add, &alpha, &dig); tot += ans[0] + ans[1] - 16; } puts!("{}\n", tot); } fn main() { // In order to avoid potential stack overflow, spawn a new thread. let stack_size = 104_857_600; // 100 MB let thd = std::thread::Builder::new().stack_size(stack_size); thd.spawn(|| solve()).unwrap().join().unwrap(); }