Problem: 2062C - Cirno and Operations
Language: java

Solution 1 (runtime: 234 ms):
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

public class Main {
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    static StringTokenizer st;

    public static String next() throws IOException {
        while (st == null || !st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    public static int nextLong() throws IOException {
        return Integer.parseInt(next());
    }

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

    public static void main(String[] args) throws IOException {
        int t = nextInt();
        while (t-- > 0) {
            run();
        }
    }

    public static void run() throws IOException {
        int n = nextInt();
        long[] arr = new long[n];
        int new_len = n;
        for(int i = 0;i<n;i++){
            arr[i] = nextLong();
        }
        long min = Long.MIN_VALUE;
        for(int i = 0;i<n;i++){
            long sum = 0;
            for(int j=0;j<new_len;j++){
                sum+=arr[j];
            }
            if(i==0){
                min = Math.max(min,sum);
            }
            else{
                min = Math.max(min,Math.max(sum,-sum));
            }
            for(int j = 0;j<n-1;j++){
                arr[j] = arr[j+1]-arr[j];
            }
            new_len--;
        }
        System.out.println(min);
    }
}


Solution 2 (runtime: 140 ms):
import java.io.*;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
import java.util.stream.Collectors;



public class Main {
    static int MOD = (int) (1e9+7);
    static InputReader in = new InputReader(System.in);
    static PrintWriter out = new PrintWriter(System.out, false);
    static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;
        public int nextInt() {
            return Integer.parseInt(next());
        }
        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 long nextLong() {
            return Long.parseLong(next());
        }

        public double nextDouble() {
            return Double.parseDouble(next());
        }
    }
    static List<Long> list = new ArrayList<>();
    public static void main(String[] args) throws Exception {

        Main main = new Main();
        int T = in.nextInt();
        while (T-- > 0){
            main.solve();
        }
        out.flush();
    }

    void solve() {
        int n = in.nextInt();
        List<Long> list = new ArrayList<>();
        long sum = 0;
        for (int i = 0; i < n; i++) {
            long t = in.nextInt();
            list.add(t);
            sum += t;
        }
        long max = sum;
        while (list.size() > 1){
            List<Long> list0 = new ArrayList<>();
            sum = 0;
            for (int i = 1; i < list.size(); i++) {
                long t = list.get(i) - list.get(i - 1);
                list0.add(t);
                sum += t;
            }
            if(sum < 0) sum *= -1;
            max = Math.max(max, sum);
            list = list0;

        }
        out.println(max);
    }





}