Hackerrank

I know it is embarassing to post code like this without asymptotic analysis. After taking a strenuous 10 week Machine learning course I am again coding java. This is the Utopia problem which can be solved in one line.

package com.hackerrank;

import java.io.*;
import java.util.ArrayList;


public class Solution {

    private int noOfTestCases;

    private ArrayList<Integer> tests = new ArrayList<>();

    OutputStream outputStream = System.out;
    PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));

    protected void parseStdin(String[] data){

        int test = Integer.parseInt( data[0] );
        assert( test >= 1 && test <= 10);
        noOfTestCases = test;
            for( int i = 1 ; i < data.length ; i ++ ){
                int d = Integer.parseInt( data[i] );
                assert( d >= 0 && d <= 60);
                tests.add( d );
            }
        assert( tests.size() == noOfTestCases );
    }


    public ArrayList<String>  getInput(BufferedReader br) throws IOException {
        String line = null;
        ArrayList<String> arguments = new ArrayList<>();
        while( (line = br.readLine()) != null ){
            arguments.add(line);
        }
        br.close();
        return arguments;
    }

    public static void main( String... argv ) throws IOException {

        Solution utopia = new Solution();
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        ArrayList<String> arguments = utopia.getInput( br );
        utopia.parseStdin( arguments.toArray(new String[arguments.size()]));
        utopia.test();


    }

    protected void test() {
        assert( 0 != noOfTestCases );
        assert( tests.size() == noOfTestCases );
        for( Integer test : tests)   {
            if( test != 0 ){
               if(test % 2  == 0){
                   growEvenly(test);
               }else{
                   growOddly(test);

               }
            }else{
                pw.println(1);
            }
        }
        pw.close();
    }

    private void growOddly(int test) {
        int odd = 1;
        if(test == 1 ){
            pw.println(test + 1);
        }else{
            for(int j = 0,k = test - 1 ; j < k; j = j + 2 ){
                odd = odd + odd + 1;
            }
            pw.println(odd * 2); pw.flush();
        }

    }

    private void growEvenly(int test) {
        int even = 1;
        for(int j = 0,k = test / 2 ; j < k ; j ++){
            even = even * 2 + 1;

        }
        pw.println(even);  pw.flush();
    }
}

Easymock

I have to expect 4 calls to readLine to accomodate null.

package com.hackerrank;

import org.junit.Assert;
import org.junit.*;

import java.io.BufferedReader;
import java.io.IOException;

import static org.easymock.EasyMock.createMock;
import static org.easymock.EasyMock.expect;
import static org.easymock.EasyMock.replay;

public class UtopiaTest {

    String[] argv;

    Solution solution;

    @Before
    public void sendInput() throws IOException {
        BufferedReader mockInputStream = createMock(BufferedReader.class);
        expect(mockInputStream.readLine()).andReturn(String.valueOf(2));
        expect(mockInputStream.readLine()).andReturn(String.valueOf(0));
        expect(mockInputStream.readLine()).andReturn(String.valueOf(1));
        expect(mockInputStream.readLine()).andReturn(null);
        replay(mockInputStream);
        solution = new Solution();
        argv = solution.getInput(mockInputStream).toArray(new String[3]);
        Assert.assertTrue(argv.length == 3);
    }

    @Test
    public void parse(){
        solution = new Solution();
        solution.parseStdin( argv );
    }

    @Test
    public void test(){
        solution = new Solution();
        solution.parseStdin( argv );
        solution.test();
    }
}

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