Merge remote-tracking branch 'upstream/master'

config.json

   "language": "Java",
   "repository": "https://github.com/exercism/xjava",
   "active": true,
+
   "exercises": [
     {
       "slug": "hello-world",
       "slug": "ocr-numbers",
       "difficulty": 1,
       "topics": []
+    },
+     {
+      "slug": "isogram",
+      "difficulty": 1,
+      "topics": []
+    },
+    {
+      "slug": "book-store",
+      "difficulty": 1,
+      "topics": []
     }
   ],
   "deprecated": [
     "say"
   ]
 }
+

exercises/book-store/build.gradle

+apply plugin: "java"
+apply plugin: "eclipse"
+apply plugin: "idea"
+
+repositories {
+  mavenCentral()
+}
+
+dependencies {
+  testCompile "junit:junit:4.12"
+}
+test {
+  testLogging {
+    exceptionFormat = 'full'
+    events = ["passed", "failed", "skipped"]
+  }
+}

exercises/book-store/src/example/java/Bookstore.java

+import java.awt.print.Printable;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class Bookstore{
+
+	private static int BOOK_PRICE = 8, MAX_GROUP_SIZE = 5;
+	private List<Integer> books;
+	private static double[] DISCOUNT_TIERS = {0,5,10,20,25};   	
+
+	public Bookstore (List<Integer> books){
+		this.books = books;
+	}	
+	
+
+
+
+	public double calculateTotalCost(){
+		return calculateTotalCost(this.books,0);
+	}
+
+	private double calculateTotalCost (List<Integer> books,double priceSoFar ){
+		double minPrice = Double.MAX_VALUE;
+
+
+		if(books.size() == 0){
+			return priceSoFar;
+		}
+
+		List<Integer> groups = (ArrayList<Integer>) books.stream().distinct().collect(Collectors.toList());
+
+		
+		double price = 0;
+
+		for(int i = 0;i<groups.size();i++){
+			books.remove(groups.get(i));	
+		}
+				
+		try {
+			price = calculateTotalCost(books,priceSoFar + costPerGroup(groups.size()));
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+		
+		minPrice = Math.min(minPrice, price);
+		return minPrice;
+
+
+	}
+
+	private double costPerGroup(int groupSize) throws Exception{
+		if (groupSize < 1 || groupSize > MAX_GROUP_SIZE){
+        		throw new Exception("Invalid group size : " + groupSize );
+     		}
+    		return BOOK_PRICE * groupSize * (100 - DISCOUNT_TIERS[groupSize-1])/100;
+	}
+
+
+}

exercises/book-store/src/test/java/BookstoreTest.java

+import static org.junit.Assert.assertEquals;
+
+import java.util.List;
+import java.util.ArrayList;
+import java.util.Arrays;
+
+import org.junit.Test;
+
+public class BookstoreTest{
+
+	@Test
+	public void onlyASingleBook(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(8,bookstore.calculateTotalCost(),2);
+	}
+	
+	@Ignore
+	@Test
+	public void twoOfSameBook(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(16,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void emptyBasket(){
+		List<Integer> books = new ArrayList<>();
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(0,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void twoDifferentBooks(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,2));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(15.20,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void threeDifferentBooks(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,2,3));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(21.6,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void fourDifferentBooks(){
+		ArrayList<Integer> books = new ArrayList<>(Arrays.asList(1,2,3,4));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(25.6,bookstore.calculateTotalCost(),2);
+
+	}
+
+	@Ignore
+	@Test
+	public void fiveDifferentBooks(){
+		ArrayList<Integer> books = new ArrayList<>(Arrays.asList(1,2,3,4,5));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(30,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void twoGroupsOfFourIsCheaperThanGroupOfFivePlusGroupOfThree(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1,2,2,3,3,4,5));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(51.20,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void groupOfFourPlusGroupOfTwoIsCheaperThanTwoGroupsOfThree(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1,2,2,3,4));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(40.8,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void twoEachOfFirst4BooksAnd1CopyEachOfRest(){
+		Integer[] p = {1,1,2,2,3,3,4,4,5};
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1,2,2,3,3,4,4,5));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(55.60,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void twoCopiesOfEachBook(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1,2,2,3,3,4,4,5,5));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(60.00,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void threeCopiesOfFirstBookAnd2EachOfRemaining(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1,2,2,3,3,4,4,5,5,1));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(68.00,bookstore.calculateTotalCost(),2);
+	}
+
+	@Ignore
+	@Test
+	public void threeEachOFirst2BooksAnd2EachOfRemainingBooks(){
+		List<Integer> books = new ArrayList<>(Arrays.asList(1,1,2,2,3,3,4,4,5,5,1,2));
+		Bookstore bookstore = new Bookstore(books);
+		assertEquals(75.20,bookstore.calculateTotalCost(),2);
+	}
+
+}
+

exercises/hamming/src/example/java/Hamming.java

 public class Hamming {
+    private final int hammingDistance;
 
-    public static int compute(String leftStrand, String rightStrand) {
+    public Hamming(String leftStrand, String rightStrand) {
+        hammingDistance = computeHammingDistance(leftStrand, rightStrand);
+    }
+
+    public int getHammingDistance() {
+        return hammingDistance;
+    }
+
+    private int computeHammingDistance(String leftStrand, String rightStrand) {
         if(leftStrand.length() != rightStrand.length()) {
             throw new IllegalArgumentException("leftStrand and rightStrand must be of equal length.");
         }
         return distance;
     }
 
-    private static int hammingContributionAt(int index, String leftStrand, String rightStrand) {
+    private int hammingContributionAt(int index, String leftStrand, String rightStrand) {
       return leftStrand.charAt(index) != rightStrand.charAt(index) ? 1 : 0;
     }
 

exercises/hamming/src/test/java/HammingTest.java

 import org.junit.rules.ExpectedException;
 
 public class HammingTest {
-    
 
     @Rule
     public ExpectedException thrown = ExpectedException.none();
     
     @Test
     public void testNoDifferenceBetweenIdenticalStrands() {
-        assertThat(Hamming.compute("A", "A"), is(0));
+        assertThat(new Hamming("A", "A").getHammingDistance(), is(0));
     }
 
     @Ignore
     @Test
     public void testHammingDistanceForSingleNucleotideStrand() {
-        assertThat(Hamming.compute("A", "G"), is(1));
+        assertThat(new Hamming("A", "G").getHammingDistance(), is(1));
     }
 
     @Ignore
     @Test
     public void testHammingDistanceForSmallStrand() {
-        assertThat(Hamming.compute("AG", "CT"), is(2)); 
+        assertThat(new Hamming("AG", "CT").getHammingDistance(), is(2));
     }
 
     @Ignore
     @Test
     public void testSmallHammingDistance() {
-        assertThat(Hamming.compute("AT", "CT"), is(1));
+        assertThat(new Hamming("AT", "CT").getHammingDistance(), is(1));
     }
 
     @Ignore
     @Test
     public void testSmallHammingDistanceInLongerStrand() {
-        assertThat(Hamming.compute("GGACG", "GGTCG"), is(1));
+        assertThat(new Hamming("GGACG", "GGTCG").getHammingDistance(), is(1));
     }
 
     @Ignore
     @Test
     public void testValidatesFirstStrandNotLonger() {
         thrown.expect(IllegalArgumentException.class);
-        Hamming.compute("AAAG", "AAA");                
+        new Hamming("AAAG", "AAA");
     }
 
     @Ignore
     @Test
     public void testValidatesOtherStrandNotLonger() {
         thrown.expect(IllegalArgumentException.class);
-        Hamming.compute("AAA", "AAAG");
+        new Hamming("AAA", "AAAG");
     }
 
     @Ignore
     @Test
     public void testLargeHammingDistance() {
-        assertThat(Hamming.compute("GATACA", "GCATAA"), is(4));
+        assertThat(new Hamming("GATACA", "GCATAA").getHammingDistance(), is(4));
     }
 
     @Ignore
     @Test
     public void testHammingDistanceInVeryLongStrand() {
-        assertThat(Hamming.compute("GGACGGATTCTG", "AGGACGGATTCT"), is(9));
+        assertThat(new Hamming("GGACGGATTCTG", "AGGACGGATTCT").getHammingDistance(), is(9));
     }
 
 }

exercises/isogram/build.gradle

+apply plugin: "java"
+apply plugin: "eclipse"
+apply plugin: "idea"
+
+repositories {
+  mavenCentral()
+}
+
+dependencies {
+  testCompile "junit:junit:4.12"
+}
+test {
+  testLogging {
+    exceptionFormat = 'full'
+    events = ["passed", "failed", "skipped"]
+  }
+}

exercises/isogram/src/example/java/IsogramChecker.java

+package example;
+
+import java.util.HashSet;
+import java.util.Set;
+import static java.util.Arrays.stream;
+import static java.util.stream.Collectors.joining;
+
+public class IsogramChecker {
+	
+	public IsogramChecker(){
+	}
+	
+	public boolean isIsogram(String word){
+		
+		Set<Character> charSet = new HashSet<>();
+		
+		String[] words = word.split(" ");
+		String newWord = concat(words);
+		
+		words = newWord.split("-");
+		newWord = concat(words).toLowerCase();
+		
+		for(int i = 0; i < newWord.length(); i++){
+			charSet.add(newWord.charAt(i));
+		}
+		
+		return charSet.size() == newWord.length();
+	}
+	
+	private String concat(String[] words){
+		return stream(words).collect(joining());
+	}
+	
+}

exercises/isogram/src/test/java/IsogramTest.java

+package test;
+
+import static org.junit.Assert.*;
+
+import org.junit.Ignore;
+import org.junit.Test;
+import example.IsogramChecker;
+
+public class IsogramTest {
+
+	@Test
+	public void testIsogram() {
+		IsogramChecker iso = new IsogramChecker();
+		assertTrue(iso.isIsogram("duplicates"));
+	}
+	
+	@Ignore
+	@Test
+	public void testNotIsogram() {
+		IsogramChecker iso = new IsogramChecker();
+		assertFalse(iso.isIsogram("eleven"));
+	}
+	
+	@Ignore
+	@Test
+	public void testMediumLongIsogram() {
+		IsogramChecker iso = new IsogramChecker();
+		assertTrue(iso.isIsogram("subdermatoglyphic"));
+	}
+	
+	@Ignore
+	@Test
+	public void testCaseInsensitive() {
+		IsogramChecker iso = new IsogramChecker();
+		assertFalse(iso.isIsogram("Alphabet"));
+	}
+	
+	@Ignore
+	@Test
+	public void testIsogramWithHyphen() {
+		IsogramChecker iso = new IsogramChecker();
+		assertTrue(iso.isIsogram("thumbscrew-japingly"));
+	}
+	
+	@Ignore
+	@Test
+	public void testIgnoresMultipleHyphens() {
+		IsogramChecker iso = new IsogramChecker();
+		assertTrue(iso.isIsogram("Hjelmqvist-Gryb-Zock-Pfund-Wax"));
+	}
+	
+	@Ignore
+	@Test
+	public void testWorksWithGermanLetters() {
+		IsogramChecker iso = new IsogramChecker();
+		assertTrue(iso.isIsogram("Heizölrückstoßabdämpfung"));
+	}
+	
+	@Ignore
+	@Test
+	public void testIgnoresSpaces() {
+		IsogramChecker iso = new IsogramChecker();
+		assertFalse(iso.isIsogram("the quick brown fox"));
+	}
+	
+	@Ignore
+	@Test
+	public void testIgnoresSpaces2() {
+		IsogramChecker iso = new IsogramChecker();
+		assertTrue(iso.isIsogram("Emily Jung Schwartzkopf"));
+	}
+	
+	@Ignore
+	@Test
+	public void testDuplicateAccentedLetters() {
+		IsogramChecker iso = new IsogramChecker();
+		assertFalse(iso.isIsogram("éléphant"));
+	}
+
+}

exercises/settings.gradle

 include 'binary-search'
 include 'binary-search-tree'
 include 'bob'
+include 'book-store'
 include 'bracket-push'
 include 'change'
 include 'clock'
 include 'hamming'
 include 'hexadecimal'
 include 'hello-world'
+include 'isogram'
 include 'largest-series-product'
 include 'linked-list'
 include 'list-ops'