Invert

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 */

//package javaapplication6;

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

/**
 *
 * @author tuukkatu
 */
public class JavaApplication6 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        
        IO io = new IO();
        
        ArrayList<Integer> list = new ArrayList();
        
        long numOfCommands = io.nextInt();
        
        int i = 0;
        
        boolean previousOperationWasFour = false;
        
        int previousNumberOfInversions = 0;
        
        while(i < numOfCommands) {
            
            int a = io.nextInt();
            
            if (a == 1 || a == 2) 
            {
                int b = io.nextInt();
                
                list = insertNumberInEnd(list, b);
                
                previousOperationWasFour = false;
            }
            else
            {
                if (a == 3)
                {
                    list = sortInNondecreasingOrder(list);
                    
                    previousOperationWasFour = false;
                }
                if (a == 4)
                {
                    if (previousOperationWasFour)
                    {
                        io.println(previousNumberOfInversions);
                    }
                    else
                    {
                        int numberOfInversions = countInversions(list);
                    
                        io.println(numberOfInversions);
                        
                        previousNumberOfInversions = numberOfInversions;
                    }
                    
                    previousOperationWasFour = true;
                }
            }
            
            
            i++;
            
            
        }
        
        
    }
    
    private static ArrayList<Integer> insertNumberInEnd(ArrayList<Integer> list,
                                                        int number)
    {
        list.add(number);
        
        return list;
    }
    
    private static ArrayList<Integer> insertNumberInBeginning(ArrayList<Integer> list,
                                                              int number)
    {
        list.add(0, number);
        
        return list;
    }
    
    private static ArrayList<Integer> sortInNondecreasingOrder(ArrayList<Integer> list)
    { 
        Collections.sort(list);
        
        Collections.reverse(list);
        
        return list;
    }
    
    private static int countInversions(ArrayList<Integer> list)
    {
        int inversionCounter = 0;
        
        if (list.size() < 2)
        {
            return 0;
        }
        
        for (int i = 0; i < list.size() - 1; i++)
        {
            for (int j = i + 1; j < list.size(); j++)
            {
                if (list.get(i) > list.get(j))
                {
                    inversionCounter++;
                }
            }
        }
        
        return inversionCounter;
    }
    
    
}

Test 1

Verdict: TIME LIMIT EXCEEDED

Test 2

Verdict: TIME LIMIT EXCEEDED

Test 3

Verdict: TIME LIMIT EXCEEDED

Test 4

Verdict: TIME LIMIT EXCEEDED

Test 5

Verdict: TIME LIMIT EXCEEDED

Test 6

Verdict: TIME LIMIT EXCEEDED

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: TIME LIMIT EXCEEDED

Test 9

Verdict: TIME LIMIT EXCEEDED

Test 10

Verdict: TIME LIMIT EXCEEDED

Test 11

Verdict: TIME LIMIT EXCEEDED

Test 12

Verdict: TIME LIMIT EXCEEDED

Test 13

Verdict: TIME LIMIT EXCEEDED

Test 14

Verdict: TIME LIMIT EXCEEDED

Test 15

Verdict: TIME LIMIT EXCEEDED

Test 16

Verdict: TIME LIMIT EXCEEDED

Test 17

Verdict: TIME LIMIT EXCEEDED

Test 18

Verdict: TIME LIMIT EXCEEDED

Test 19

Verdict: TIME LIMIT EXCEEDED

Test 20

Verdict: TIME LIMIT EXCEEDED