macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    ($($r:tt)*) => {
        #[allow(unused_mut)]
        let mut 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)*) => {
        #[allow(non_snake_case)]
        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::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}

#[allow(unused_macros)]
macro_rules! debug {
    ($($a:expr),*) => {
        eprintln!(concat!($(stringify!($a), " = {:?}, "),*), $($a),*);
    }
}

use std::cmp;

fn main() {
    input! {
        v: [usize; 4],
    }
    // dp[k]: 長さ k の板を作るのに必要な板の最小枚数
    let inf = 31;
    let mut ans = inf;
    let mut dp = vec![0; 31];
    for a in 1..31 {
        for b in 1..a {
            for c in 1..b {
                dp[0] = 0;
                for i in 1..31 {
                    dp[i] = inf;
                }
                for len in &[a, b, c] {
                    for i in *len..31 {
                        dp[i] = cmp::min(dp[i-len] + 1, dp[i]);
                    }
                }
                let mut sum = 0;
                for x in &v {
                    sum += dp[*x];
                }
                ans = cmp::min(sum, ans);
            }
        }
    }
    println!("{}", ans);
}