Secret society

import java.util.ArrayList;
import java.util.Collections;

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author viljampa
 */
public class Kilpa31 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        IO io = new IO();
        ArrayList<Integer> lista = new ArrayList();
        long summa = 0;
        long summa2 = 0;
        
        int koko = io.nextInt();
        for (int i = 0; i < koko; i++) {
            lista.add(io.nextInt());
        }
        
//        int koko = 6;
//        for (int i = 0; i < 100000; i++) {
//            lista.add(100000);
//        }
//        lista.add(1);
//        lista.add(2);
//        lista.add(3);
////        lista.add(6);
//        lista.add(1);
//        lista.add(9);
//        lista.add(9);
//        lista.add(4);
//        lista.add(1);
//        lista.add(7);
////        lista.add(5);
//        lista.add(2);
//        lista.add(6);
//        lista.add(3);
//        lista.add(3);
//        lista.add(7);
////        lista.add(2);
////        lista.add(3);
//        lista.add(2);
//        lista.add(10);
//        lista.add(7);
//        lista.add(1);
        
        int kohta = 0;
        for (int i = 0; i < koko - 2;) {
            if (lista.get(i) + lista.get(i + 2) < lista.get(i + 1)) {
                summa += lista.get(i + 1);
                i += 3;
            } else {
                summa += lista.get(i);
                i += 2;
            }
            kohta = i;
        }
        if (kohta == koko - 1) summa += lista.get(koko - 1);
        else if (kohta == koko - 2) {
            if (lista.get(koko - 1) > lista.get(koko - 2)) summa += lista.get(koko - 1);
            else summa += lista.get(koko - 2);
        }
        
        Collections.reverse(lista);
        
        int kohta2 = 0;
        for (int i = 0; i < koko - 2;) {
            if (lista.get(i) + lista.get(i + 2) < lista.get(i + 1)) {
                summa2 += lista.get(i + 1);
                i += 3;
            } else {
                summa2 += lista.get(i);
                i += 2;
            }
            kohta2 = i;
        }
        if (kohta2 == koko - 1) summa2 += lista.get(koko - 1);
        else if (kohta2 == koko - 2) {
            if (lista.get(koko - 1) > lista.get(koko - 2)) summa2 += lista.get(koko - 1);
            else summa2 += lista.get(koko - 2);
        }
        
        if (koko == 2) {
            if (lista.get(0) > lista.get(1)) {
                summa = lista.get(0);
                summa2 = lista.get(0);
            }
            else {
                summa = lista.get(1);
                summa2 = lista.get(1);
            }
        }
        long isompi = 0;
        if (summa > summa2) {
            isompi = summa;
        } else {
            isompi = summa2;
        }
        io.print(isompi);
        io.close();

//	String a = io.next(); // Lukee seuraavan välein erotellun merkkijonon.
//	int b = io.nextInt(); // Lukee seuraavan välein erotellun int-kokonaisluvun.
//	long c = io.nextLong(); // Lukee seuraavan välein erotellun long-kokonaisluvun.
//	double d = io.nextDouble(); // Lukee seuraavan välein erotellun double-liukuluvun.
    }
    
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: WRONG ANSWER

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED

Test 28

Verdict: ACCEPTED

Test 29

Verdict: ACCEPTED

Test 30

Verdict: ACCEPTED

Test 31

Verdict: WRONG ANSWER

Test 32

Verdict: WRONG ANSWER

Test 33

Verdict: WRONG ANSWER

Test 34

Verdict: WRONG ANSWER

Test 35

Verdict: WRONG ANSWER

Test 36

Verdict: WRONG ANSWER

Test 37

Verdict: WRONG ANSWER

Test 38

Verdict: WRONG ANSWER

Test 39

Verdict: WRONG ANSWER

Test 40

Verdict: WRONG ANSWER

Test 41

Verdict: WRONG ANSWER

Test 42

Verdict: WRONG ANSWER

Test 43

Verdict: WRONG ANSWER

Test 44

Verdict: WRONG ANSWER

Test 45

Verdict: WRONG ANSWER

Test 46

Verdict: WRONG ANSWER

Test 47

Verdict: WRONG ANSWER

Test 48

Verdict: WRONG ANSWER

Test 49

Verdict: WRONG ANSWER

Test 50

Verdict: WRONG ANSWER

Test 51

Verdict: WRONG ANSWER

Test 52

Verdict: WRONG ANSWER

Test 53

Verdict: WRONG ANSWER

Test 54

Verdict: WRONG ANSWER

Test 55

Verdict: WRONG ANSWER

Test 56

Verdict: WRONG ANSWER

Test 57

Verdict: WRONG ANSWER

Test 58

Verdict: WRONG ANSWER

Test 59

Verdict: WRONG ANSWER

Test 60

Verdict: WRONG ANSWER