// Original: https://github.com/tanakh/competitive-rs #[allow(unused_macros)] macro_rules! input { (source = $s:expr, $($r:tt)*) => { let mut iter = $s.split_whitespace(); let mut next = || { iter.next().unwrap() }; input_inner!{next, $($r)*} }; ($($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)*} }; } #[allow(unused_macros)] 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)*} }; ($next:expr, mut $var:ident : $t:tt $($r:tt)*) => { let mut $var = read_value!($next, $t); input_inner!{$next $($r)*} }; } #[allow(unused_macros)] macro_rules! read_value { ($next:expr, ( $($t:tt),* )) => { ( $(read_value!($next, $t)),* ) }; ($next:expr, [ $t:tt ; $len:expr ]) => { (0..$len).map(|_| read_value!($next, $t)).collect::>() }; ($next:expr, [ $t:tt ]) => { { let len = read_value!($next, usize); (0..len).map(|_| read_value!($next, $t)).collect::>() } }; ($next:expr, chars) => { read_value!($next, String).chars().collect::>() }; ($next:expr, bytes) => { read_value!($next, String).into_bytes() }; ($next:expr, usize1) => { read_value!($next, usize) - 1 }; ($next:expr, $t:ty) => { $next().parse::<$t>().expect("Parse error") }; } #[allow(dead_code)] fn chmin(x: &mut T, y: T) -> bool where T: PartialOrd + Copy, { *x > y && { *x = y; true } } #[allow(dead_code)] fn chmax(x: &mut T, y: T) -> bool where T: PartialOrd + Copy, { *x < y && { *x = y; true } } mod mod_int { use std::ops::*; pub trait Mod: Copy { fn m() -> i64; } #[derive(Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)] pub struct ModInt { pub val: i64, phantom: std::marker::PhantomData, } impl ModInt { // x >= 0 pub fn new(val: i64) -> Self { ModInt::new_internal(val % M::m()) } fn new_internal(val: i64) -> Self { ModInt { val: val, phantom: std::marker::PhantomData, } } pub fn pow(self, mut e: i64) -> Self { debug_assert!(e >= 0); let mut sum = ModInt::new_internal(1); let mut cur = self; while e > 0 { if e % 2 != 0 { sum *= cur; } cur *= cur; e /= 2; } sum } // mod m における self.val の逆元 #[allow(dead_code)] pub fn inv(self) -> Self { self.pow(M::m() - 2) } } impl>> Add for ModInt { type Output = Self; fn add(self, other: T) -> Self { let other = other.into(); let mut sum = self.val + other.val; if sum >= M::m() { sum -= M::m(); } ModInt::new_internal(sum) } } impl>> Sub for ModInt { type Output = Self; fn sub(self, other: T) -> Self { let other = other.into(); let mut sum = self.val - other.val; if sum < 0 { sum += M::m(); } ModInt::new_internal(sum) } } impl>> Mul for ModInt { type Output = Self; fn mul(self, other: T) -> Self { ModInt::new_internal(self.val * other.into().val % M::m()) } } impl>> AddAssign for ModInt { fn add_assign(&mut self, other: T) { *self = *self + other; } } impl>> SubAssign for ModInt { fn sub_assign(&mut self, other: T) { *self = *self - other; } } impl>> MulAssign for ModInt { fn mul_assign(&mut self, other: T) { *self = *self * other; } } impl Neg for ModInt { type Output = Self; fn neg(self) -> Self { ModInt::new(0) - self } } impl std::fmt::Display for ModInt { fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result { self.val.fmt(f) } } impl std::fmt::Debug for ModInt { fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result { let (mut a, mut b, _) = red(self.val, M::m()); if b < 0 { a = -a; b = -b; } write!(f, "{}/{}", a, b) } } impl From for ModInt { fn from(val: i64) -> Self { Self::new(val) } } // Finds the simplest fraction x/y congruent to r mod p. // The return value (x, y, z) satisfies x = y * r + z * p. fn red(r: i64, p: i64) -> (i64, i64, i64) { if r.abs() <= 10000 { return (r, 1, 0); } let mut nxt_r = p % r; let mut q = p / r; if 2 * nxt_r >= r { nxt_r -= r; q += 1; } if 2 * nxt_r <= -r { nxt_r += r; q -= 1; } let (x, z, y) = red(nxt_r, r); (x, y - q * z, z) } } // mod mod_int macro_rules! define_mod { ($struct_name: ident, $modulo: expr) => { #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)] struct $struct_name {} impl mod_int::Mod for $struct_name { fn m() -> i64 { $modulo } } }; } const MOD: i64 = 1e9 as i64 + 7; define_mod!(P, MOD); type ModInt = mod_int::ModInt

; mod mod_comb { use super::ModInt; pub struct BiCoef { fact: Vec, invfact: Vec, } impl BiCoef { pub fn new(n: usize) -> Self { let mut fact: Vec = vec![1.into(); n + 1]; let mut invfact: Vec = vec![1.into(); n + 1]; for i in 0..n { fact[i + 1] = fact[i] * ModInt::new(i as i64 + 1); } invfact[n] = fact[n].inv(); for i in (0..n).rev() { invfact[i] = invfact[i + 1] * ModInt::new(i as i64 + 1); } BiCoef { fact: fact, invfact: invfact, } } pub fn fact(&self, n: usize) -> ModInt { if let Some(x) = self.fact.get(n) { *x } else if n >= super::MOD as usize { ModInt::new(0) } else { let mut res = 1.into(); for i in 1..(n + 1) { res *= ModInt::new(i as i64 + 1); } res } } pub fn invfact(&self, n: usize) -> ModInt { if let Some(x) = self.invfact.get(n as usize) { *x } else { self.fact(n).inv() } } #[doc = " `nPr = n! / (n - r)!`"] #[doc = ""] #[doc = " `O(1)` if n and r are smaller than input in `new` method."] pub fn perm(&self, n: i64, r: i64) -> ModInt { if n >= r { self.fact(n as usize) * self.invfact((n - r) as usize) } else { 0.into() } } #[doc = " `nCr = n! / (n - r)! / r!`."] #[doc = ""] #[doc = " `O(1)` if n and r are smaller than input in `new` method."] pub fn comb(&self, n: i64, r: i64) -> ModInt { if n >= r { self.fact(n as usize) * self.invfact((n - r) as usize) * self.invfact(r as usize) } else { ModInt::from(0) } } #[doc = " `(n + k - 1)! / k!`."] #[doc = ""] #[doc = " `O(1)` if n and r are smaller than input in `new` method."] pub fn multi_comb(&self, n: i64, r: i64) -> ModInt { if r == 0 { ModInt::from(1) } else { self.comb(n + r - 1, r) } } } } #[allow(unused_imports)] use std::cmp::{max, min}; #[allow(unused_imports)] use std::collections::{BTreeMap, BTreeSet, BinaryHeap, VecDeque}; fn main() { input!(n: usize); use mod_comb::*; let bi = BiCoef::new(n); if n >= MOD as usize { println!("0"); } else { println!("{}", bi.fact(n)); } }