use itertools::Itertools;
use proconio::input;

fn main() {
    input! {
        a: [usize; 13],
    }

    let mut count = [0; 10];
    for &a in &a {
        count[a] += 1;
    }

    let ans = (1..10)
        .filter(|&x| {
            let mut count = count;
            count[x] += 1;
            count.sort_unstable();
            count == [0, 0, 0, 0, 0, 2, 3, 3, 3, 3]
        })
        .collect_vec();

    println!("{}", ans.len());
    println!("{}", ans.iter().join(" "));
}