fn main() {
    input! {
        n: usize,
        s: bytes,
    }
    let mut cnt = [0i32; 10];
    for c in s {
        cnt[(c - b'0') as usize] += 1;
    }
    let a = std::cell::RefCell::new(vec![]);
    recurse(|rec, (cnt, d, m): ([i32; 10], usize, usize)| {
        if d >= 3 || cnt.iter().all(|c| *c == 0) {
            a.borrow_mut().push(m % 40);
            return;
        }
        for i in 1..10 {
            if cnt[i] > 0 {
                let mut cnt = cnt;
                cnt[i] -= 1;
                rec((cnt, d + 1, 10 * m + i));
            }
        }
    })((cnt, 0, 0));
    let mut a = a.into_inner();
    a.sort();
    a.dedup();
    println!("{}", a.len());
}

// ---------- begin recurse ----------
// reference
// https://twitter.com/noshi91/status/1393952665566994434
// https://twitter.com/shino16_cp/status/1393933468082397190
pub fn recurse<A, R, F>(f: F) -> impl Fn(A) -> R
where
    F: Fn(&dyn Fn(A) -> R, A) -> R,
{
    fn call<A, R, F>(f: &F, a: A) -> R
    where
        F: Fn(&dyn Fn(A) -> R, A) -> R,
    {
        f(&|a| call(f, a), a)
    }
    move |a| call(&f, a)
}
// ---------- end recurse ----------
// ---------- begin input macro ----------
// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
#[macro_export]
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_export]
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_export]
macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };
    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };
    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };
    ($iter:expr, bytes) => {
        read_value!($iter, String).bytes().collect::<Vec<u8>>()
    };
    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };
    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}
// ---------- end input macro ----------