use std::collections::*; use std::io::Read; fn get_word() -> String { let stdin = std::io::stdin(); let mut stdin=stdin.lock(); let mut u8b: [u8; 1] = [0]; loop { let mut buf: Vec = Vec::with_capacity(16); loop { let res = stdin.read(&mut u8b); if res.unwrap_or(0) == 0 || u8b[0] <= b' ' { break; } else { buf.push(u8b[0]); } } if buf.len() >= 1 { let ret = String::from_utf8(buf).unwrap(); return ret; } } } #[allow(dead_code)] fn get() -> T { get_word().parse().ok().unwrap() } fn dfs(n: i64, k: i64, memo: &mut HashMap<(i64, i64), u64>) -> u64 { if let Some(&val) = memo.get(&(n, k)) { return val; } if k <= 0 { return 0; } if n <= 0 { return 0; } let mut sum = if k >= n { 1 } else { 0 }; if k >= n { sum += dfs(n - 1, k / n, memo); } sum += dfs(n - 1, k, memo); memo.insert((n, k), sum); sum } fn main() { let n: i64 = get(); let k: i64 = get(); let mut memo = HashMap::new(); println!("{}", dfs(n, k, &mut memo)); }