// ---------- begin bitwise transform ---------- fn bitwise_transform(a: &mut [T], mut f: F) where F: FnMut(&mut T, &mut T) { let n = a.len().trailing_zeros() as usize; assert!(a.len() == 1 << n); for i in 0..n { for a in a.chunks_exact_mut(2 << i) { let (x, y) = a.split_at_mut(1 << i); for (x, y) in x.iter_mut().zip(y) { f(x, y); } } } } // ---------- end bitwise transform ---------- // ---------- begin input macro ---------- // reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8 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, bytes) => { read_value!($iter, String).bytes().collect::>() }; ($iter:expr, usize1) => { read_value!($iter, usize) - 1 }; ($iter:expr, $t:ty) => { $iter.next().unwrap().parse::<$t>().expect("Parse error") }; } // ---------- end input macro ---------- fn run() { input! { m: usize, n: usize, s: [usize; n * m], } let mut cnt = vec![0; 1 << n]; for s in s.chunks(n) { cnt[s.iter().fold(0, |s, a| 2 * s + *a)] += 1; } bitwise_transform(&mut cnt, |a, b| *a += *b); let mut dp = vec![0u64; 1 << n]; dp[(1 << n) - 1] = 1; for i in (1..(1 << n)).rev() { for j in 0..n { if i >> j & 1 == 1 && 2 * cnt[i] >= cnt[i ^ (1 << j)] { dp[i ^ (1 << j)] += dp[i]; } } } println!("{}", dp[0]); } fn main() { run(); }