fn main() { let alphas = get::vals::(26); let ord = |c| c as usize - 'a' as usize; let d = Combination::new(alphas[ord('d')]).comb(1); let e = Combination::new(alphas[ord('e')]).comb(1); let h = Combination::new(alphas[ord('h')]).comb(1); let l = Combination::new(alphas[ord('l')]-1).comb(3-1); let o = Combination::new(alphas[ord('o')]-1).comb(2-1); let r = Combination::new(alphas[ord('r')]).comb(1); let w = Combination::new(alphas[ord('w')]).comb(1); println!("{}", d*e*h*l*o*e*r*w) } struct Combination { n: u64, fact_table: Vec } #[allow(dead_code)] impl Combination { fn new(n: u64) -> Combination { Combination { n: n, fact_table: (1..n+1).scan(1,|a,x|{*a=modulo::mul(*a,x); Some(*a)}).collect::>() } } fn comb(&self, r: u64) -> u64 { match r { _ if self.n < r => 0, _ if self.n == r => 1, _ => { let a = self.fact_table[self.n as usize - 1]; let b = modulo::pow(self.fact_table[r as usize - 1], modulo::MOD-2); let c = modulo::pow(self.fact_table[(self.n - r) as usize - 1], modulo::MOD-2); [a,b,c].iter().fold(1, |a,&x| modulo::mul(a,x)) } } } } #[allow(dead_code)] mod modulo { pub const MOD: u64 = 1_000_000_007; pub fn plus(x: u64, y: u64) -> u64 { (x + y) % MOD } pub fn mul(x: u64, y: u64) -> u64 { (x * y) % MOD } pub fn pow(x: u64, n: u64) -> u64 { match n { 0 => 1, _ if n % 2 == 1 => mul(x, pow(x, n-1)), _ => { let q = pow(x, n>>1); mul(q, q) } } } } #[allow(dead_code)] mod get { use std::io::*; use std::str::*; pub fn val() -> T { let mut buf = String::new(); let s = stdin(); s.lock().read_line(&mut buf).ok(); buf.trim_right().parse::().ok().unwrap() } pub fn vals(n: usize) -> Vec { let mut vec: Vec = vec![]; for _ in 0 .. n { vec.push(val()); } vec } pub fn tuple() -> (T1, T2) { let mut buf = String::new(); let s = stdin(); s.lock().read_line(&mut buf).ok(); let mut it = buf.trim_right().split_whitespace(); let x = it.next().unwrap().parse::().ok().unwrap(); let y = it.next().unwrap().parse::().ok().unwrap(); (x, y) } pub fn tuples(n: usize) -> Vec<(T1, T2)> { let mut vec: Vec<(T1, T2)> = vec![]; for _ in 0 .. n { vec.push(tuple()); } vec } pub fn tuple3() -> (T1, T2, T3) { let mut buf = String::new(); let s = stdin(); s.lock().read_line(&mut buf).ok(); let mut it = buf.trim_right().split_whitespace(); let x = it.next().unwrap().parse::().ok().unwrap(); let y = it.next().unwrap().parse::().ok().unwrap(); let z = it.next().unwrap().parse::().ok().unwrap(); (x, y, z) } pub fn tuple3s(n: usize) -> Vec<(T1, T2, T3)> { let mut vec: Vec<(T1, T2, T3)> = vec![]; for _ in 0 .. n { vec.push(tuple3()); } vec } pub fn list() -> Vec { let mut buf = String::new(); let s = stdin(); s.lock().read_line(&mut buf).ok(); buf.trim_right().split_whitespace().map(|t| t.parse::().ok().unwrap()).collect() } pub fn lists(h: usize) -> Vec> { let mut mat: Vec> = vec![]; for _ in 0 .. h { mat.push(list()); } mat } pub fn chars() -> Vec { let mut buf = String::new(); let s = stdin(); s.lock().read_line(&mut buf).ok(); buf.trim_right().chars().collect() } }