15.1.java

import java.util.ArrayList;

public class BaseballPlayer {
   public ArrayList<Integer> playerStats;

   public BaseballPlayer(int numHits, int numRuns, int numRBIs) {
      playerStats = new ArrayList<Integer>();
      playerStats.add(numHits);
      playerStats.add(numRuns);
      playerStats.add(numRBIs);
   }

   public int fixPlayerList(ArrayList<String> baseballPlayers) {
      ArrayList<String> uniques = new ArrayList<String>();
      int start = baseballPlayers.size();
      for (int i = 0; i < baseballPlayers.size(); i++) {
         if (!uniques.contains(baseballPlayers.get(i))) {
            uniques.add(baseballPlayers.get(i));  
         } else {
            baseballPlayers.remove(i);
            i--;
         }
      }
      return start - baseballPlayers.size();
   }
}

15.2.java

import java.util.ArrayList;

public class FlightSchedule {
   public ArrayList<String> scheduleList;

   public FlightSchedule(ArrayList<String> flightScheduleList) {
      scheduleList = flightScheduleList;
   }

   public void delayedFlight(int delayedIndex) {
      this.scheduleList.add(scheduleList.remove(delayedIndex) + " (DELAYED)");
      System.out.println(scheduleList);
   }

   public void earlyFlight(int earlyIndex, int newPos) {
      this.scheduleList.add(newPos, scheduleList.remove(earlyIndex) + " (EARLY)");       
   }
}

15.3.java

import java.util.ArrayList;
import java.util.Map;
import java.util.HashMap;

public class FriendsList {
   ArrayList<String> friendsArray = new ArrayList<String>();
   Map<String, Integer> map = new HashMap<String, Integer>();
   public FriendsList(ArrayList<String> facebookFriends) {
      this.friendsArray = facebookFriends;
   }    
          
   public String occursMost() {
      String maxName = null;
      int max = 0;
      for (int i = 0; i < friendsArray.size(); i++) {
         if (map.containsKey(friendsArray.get(i))) {
            map.put(friendsArray.get(i), map.get(friendsArray.get(i)) + 1);
         } else {
            map.put(friendsArray.get(i), 1);
         }
         int val = map.get(friendsArray.get(i));
         if (val > max) {
            max = val;
            maxName = friendsArray.get(i);
         }
      }
      return maxName;
   }     
           
   public ArrayList<String> removeDoubles() {
      ArrayList<String> uniques = new ArrayList<String>();
      for (int i = 0; i < friendsArray.size(); i++) {
         if (!uniques.contains(friendsArray.get(i))) {
            uniques.add(friendsArray.get(i));  
         }
      }
      friendsArray = uniques;
      return friendsArray;
   }                  
}

15.4.java

import java.util.ArrayList;

public class TheOffice {
   public double getRealPrice(double taxPercent, double salePrice) {
      return salePrice + ((0.01 * taxPercent) * salePrice);
   }
         
   public int findRundownIndex(ArrayList<String> rundown, String name) {
      for (int i = 0; i < rundown.size(); i++) {
         if (rundown.get(i).equals(name)) {
            return i;  
         }
      }
      return -1;
   }
}

15.5.java

import java.util.ArrayList;

public class TrappedHelper {
   public void removeEvens(ArrayList<Integer> arr) {
      for (int i = 0; i < arr.size(); i++) {
         if (arr.get(i) % 2 == 0) {
            arr.remove(i--);
         }
      }
   }
         
   public void removeThreeMults(ArrayList<Integer> arr) {
      for (int i = 0; i < arr.size(); i++) {
         if (arr.get(i) % 3 == 0) {
            arr.remove(i--);
         }
      }
   }
         
   public void thirdThing(ArrayList<Integer> arr) {
      for (int i = 0; i < arr.size(); i++) {   
         if (arr.get(i) % 2 == 0 && ((arr.size() - 1 != i) ? (arr.get(i+1) % 2 == 1) : false)) {
            arr.remove(i+1);  
         }
      }
   }
}

15.6.java

import java.util.ArrayList;
 
public class PhoneContacts {
   ArrayList<Integer> phoneNumbers = new ArrayList<Integer>();           
   ArrayList<String> phoneNames = new ArrayList<String>();
 
   public void addContact(String name, int number) {
      phoneNames.add(name);
      phoneNumbers.add(number);
      System.out.print(name + " was saved.");
   }
 
   public void findNumber(String name) {
      for (int i = 0; i < phoneNumbers.size(); i++) {
         if (phoneNames.contains(name)) {
            System.out.print(phoneNumbers.get(i));
            return;
         }
      }
      System.out.println("Contact doesn't exist.");
      return;
   }
 
   public void deleteContact(String name) {
      for (int i = 0; i < phoneNumbers.size(); i++) {
         if (phoneNames.contains(name)) {
            phoneNumbers.remove(i);
            phoneNames.remove(i);
            System.out.print(name + " was deleted.");
            return;
         }
      }
      System.out.print("Contact doesn't exist.");
      return;
   }
}