submitting

PlaylistChallenge.iml

@@ -13,5 +13,9 @@
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" scope="TEST" name="Maven: junit:junit:4.12" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: org.hamcrest:hamcrest-core:1.3" level="project" />
+    <orderEntry type="library" scope="TEST" name="Maven: junit:junit:4.12" level="project" />
+    <orderEntry type="library" scope="TEST" name="Maven: org.hamcrest:hamcrest-core:1.3" level="project" />
+    <orderEntry type="library" name="Maven: junit:junit:4.12" level="project" />
+    <orderEntry type="library" name="Maven: org.hamcrest:hamcrest-core:1.3" level="project" />
   </component>
 </module>

pom.xml

@@ -16,5 +16,10 @@
             <version>4.12</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>RELEASE</version>
+        </dependency>
     </dependencies>
 </project>

src/main/java/io/zipcoder/Music.java

@@ -1,14 +1,48 @@
 package io.zipcoder;
 
+
 public class Music {
 
     private String[] playList;
 
-    public Music(String[] playList){
+    public Music(String[] playList) {
         this.playList = playList;
     }
 
-    public Integer selection(Integer startIndex, String selection){
+    public Integer selection(Integer startIndex, String selection) {
+
+
+        int indexOfSelection = 0;
+
+        for (int i = 0; i < playList.length; i++) {
+
+            if (playList[i].equals(selection) && (playList.length - i < startIndex + i)) {
+                indexOfSelection += i;
+            }
+        }
+
+        //if startIndex is BEFORE the indexSelection
+        // [startIndex           selectionIndex]
+
+        if (indexOfSelection > startIndex) {
+
+            //(left side count VS right side count)
+            if (indexOfSelection - startIndex < (startIndex + playList.length - indexOfSelection)) {
+                return indexOfSelection - startIndex;
+            }
+            return startIndex + playList.length - indexOfSelection;
+        }
+
+        //if startIndex is AFTER the indexSelection
+        // [selectionIndex        startIndex]
+        if (indexOfSelection < startIndex) {
+
+            //(left side count VS right side count)
+            if (startIndex - indexOfSelection < (indexOfSelection + playList.length - startIndex)) {
+                return indexOfSelection + playList.length - startIndex;
+            }
+            return startIndex - indexOfSelection;
+        }
         return null;
     }
-}
+}