//189A : CUT RIBBON

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.StringTokenizer;

//Your code goes here
public class Main {

    static class ProblemSolver{
        public void solveTheProblem(InputReader in,PrintWriter out){
            //Take the necessary inputs
            int n=in.nextInt();
            int a=in.nextInt();
            int b=in.nextInt();
            int c=in.nextInt();
            int[] dp=new int[4001];

            //Fill all the default entry of the dp as -1 as done in most of the cases
            for(int i=0;i<=n;++i)dp[i]=-1;

            //Initialize the given data in the dp
            dp[a]=1;
            dp[b]=1;
            dp[c]=1;

            //Evaluate and take the optimal of all
            for(int i=Math.min(a, Math.min(b, c));i<=n;++i){
                if(i-a>=0 && dp[i-a]!=-1)dp[i]=Math.max(dp[i-a]+1,dp[i]);
                if(i-b>=0 && dp[i-b]!=-1)dp[i]=Math.max(dp[i-b]+1,dp[i]);
                if(i-c>=0 && dp[i-c]!=-1)dp[i]=Math.max(dp[i-c]+1,dp[i]);
            }

            //Print the result
            System.out.println(dp[n]);

        }
    }

    //Default template for all the codes
    static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream),32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

    }

    //Main method for all the codes
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        ProblemSolver problemSolver = new ProblemSolver();
        problemSolver.solveTheProblem(in, out);
        out.close();
    }

}