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

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author cplayer
 */
public class Main {
    public static void main (String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        BResale solver = new BResale();
        solver.solve(1, in, out);
        out.close();
    }

    static class BResale {
        public void solve (int testNumber, InputReader in, PrintWriter out) {
            int n = in.nextInt();
            int[] v = in.nextIntArr(n), c = in.nextIntArr(n);
            int[][] dp = new int[n][2];
            dp[0][0] = 0;
            dp[0][1] = v[0] - c[0];
            for (int i = 1; i < n; ++i) {
                dp[i][0] = Math.max(dp[i - 1][0], dp[i - 1][1]);
                dp[i][1] = Math.max(dp[i - 1][0], dp[i - 1][1]) + v[i] - c[i];
            }
            out.println(Math.max(dp[n - 1][1], dp[n - 1][0]));
        }

    }

    static class InputReader {
        private BufferedReader reader;
        private StringTokenizer tokenizer;

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

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

        public int[] nextIntArr (int length) {
            int[] res = new int[length];
            for (int i = 0; i < length; ++i) {
                res[i] = nextInt();
            }
            return res;
        }

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

    }
}


/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz