use std::cmp::min; const DIVISOR: u64 = 998244353; fn power(base: u64, p: u64) -> u64 { if p == 0 { return 1; } if p == 1 { return base; } let temp = power(base, p/2); temp * temp % DIVISOR * base % DIVISOR } fn comb(n: u64, r: u64, memo: &mut Vec>) -> u64 { if r == 0 || r == n { return 1u64; } let mut result = 1u64; for i in 1..=r { result *= n + 1 - i; result %= DIVISOR; if memo[r as usize].is_none() { memo[r as usize] = Some(power(r, DIVISOR - 2)); } result *= memo[r as usize].unwrap(); result %= DIVISOR; } result } fn main() { let mut nm = String::new(); std::io::stdin().read_line(&mut nm).ok(); let nm: Vec = nm.trim().split_whitespace().map(|s| s.parse().unwrap()).collect(); let n = nm[0]; let m = nm[1]; let mut result: u64 = 0; let mut memo: Vec> = vec![None; m as usize + 1usize]; for i in 0..=m/n { let base = m + i - i * n; result += comb(base, min(base - i, i), &mut memo); result %= DIVISOR; } println!("{}", result); }