Even_More_Pizza using Java

Google/Even_More_Pizza.java

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+import java.io.*;
+import java.util.*;
+
+class Solution_Second
+{
+  //Object representations of the pizzas which have been prepared.
+  static ArrayList<Pizza> pizzas = new ArrayList<Pizza>();
+
+  //Object representations of the deliveries which are to be made.
+  static ArrayList<Delivery> deliveries = new ArrayList<Delivery>();
+
+  //List of files to be processed.
+  static String in_files[] = {"a_example", "b_little_bit_of_everything", "c_many_ingredients", "d_many_pizzas", "e_many_teams"};
+
+  //Total number of pizzas.
+  static int total;
+
+  //Stores the number of teams 0->4 and 2->2.
+  static int teams[] = new int[3];
+
+  //Starting point of execution.
+  public static void main(String args[]) throws Exception
+  {
+    for(int i = 0; i < in_files.length; i++)
+    {
+      System.out.println("Running for file " + in_files[i]);
+
+      prepareData(in_files[i]);
+      initializeDeliveries();
+      computeScores();
+      produceOutputs(in_files[i]);
+
+      //Re-initializing variables.
+      pizzas = new ArrayList<Pizza>();
+      deliveries = new ArrayList<Delivery>();
+    }
+  }
+
+  //Write the outputs to a file.
+  public static void produceOutputs(String fileName) throws Exception
+  {
+    FileWriter fw = new FileWriter(fileName + ".out");
+    fw.write(deliveries.size() + "\n");
+    for(int i = 0; i < deliveries.size(); i++)
+    {
+      Delivery current = deliveries.get(i);
+      fw.write(current.orders + current.order_list + "\n");
+    }
+    fw.close();
+  }
+
+  //Compute the scores and make deliveries.
+  public static void computeScores()
+  {
+    //Blocks to be computed at a time.
+    int block = 2;
+
+    //Loop variable.
+    //False, if no delivery object has been modified.
+    boolean d_modified = true;
+
+    while(d_modified)
+    {
+      d_modified = false;
+      for(int i = 0; i < deliveries.size(); i++)
+      {
+        Delivery d = deliveries.get(i);
+        d.cache = new double[pizzas.size()];
+
+        if(d.c_orders < d.orders && !d_modified)
+        {d_modified = true;}
+
+        //Step: Number of pizzas to be added to the delivery at this point.
+        //Related to block.
+        int step = (block <= d.orders - d.c_orders)?block:d.orders - d.c_orders;
+        for(int j = 0; j < step; j++)
+        {
+          d.p_id = -1;
+          d.h_score = -1;
+
+          for(int k = 0; k < pizzas.size(); k++)
+          {
+            //Create relative scores for each pizza.
+            //Update if better.
+            double temp = d.pizzaScore(pizzas.get(k), k);
+            if(temp > d.h_score)
+            {
+              d.p_id = k;
+              d.h_score = temp;
+            }
+          }
+
+          //Process the selected pizza.
+          //And deliver it. (Add it to the delivery).
+          Pizza to_be_sent = pizzas.get(d.p_id);
+
+          //Ingredients to be added/sent.
+          String tbs_ings[] = to_be_sent.ingredients.split(" ");
+          d.order_list = d.order_list + " " + to_be_sent.index;
+          for(String ing : tbs_ings)
+          {
+            if(d.ingredients.indexOf(ing) == -1)
+            {
+              d.ingredients = d.ingredients + " " + ing;
+              d.count++;
+            }
+          }
+          //Remove added pizza from list.
+          pizzas.remove(to_be_sent);
+          d.c_orders++;
+        }
+        d.cache = null;
+      }
+    }
+  }
+
+  //Select the teams and initialize the delivery objects.
+  private static void initializeDeliveries()
+  {
+    int t_orders = 4;
+    while(true)
+    {
+      //Change the team size and continue, or exit.
+      if(total - t_orders < 0 || teams[4 - t_orders] - 1 < 0)
+      {
+        t_orders--;
+        if(t_orders < 2){return;}
+        continue;
+      }
+      Delivery c_delivery = new Delivery(t_orders);
+      deliveries.add(c_delivery);
+      total -= t_orders;
+      teams[4 - t_orders]--;
+    }
+  }
+
+  //Read data from the file and prepare it.
+  private static void prepareData(String fileName) throws Exception
+  {
+    BufferedReader Rb = new BufferedReader(new FileReader(fileName));
+
+    String str = Rb.readLine();
+    String temp[] = str.split(" ");
+    total = Integer.valueOf(temp[0]);
+    teams[2] = Integer.valueOf(temp[1]);
+    teams[1] = Integer.valueOf(temp[2]);
+    teams[0] = Integer.valueOf(temp[3]);
+
+    int index_counter = 0;
+    while((str = Rb.readLine()) != null)
+    {
+      temp[0] = str.substring(0, str.indexOf(" "));
+      str = str.substring(str.indexOf(" ") + 1);
+      temp[1] = str;
+
+      Pizza c_pizza = new Pizza();
+      c_pizza.count = Integer.valueOf(temp[0]);
+      c_pizza.ingredients = temp[1];
+      c_pizza.index = index_counter;
+      pizzas.add(c_pizza);
+      index_counter++;
+    }
+    Rb.close();
+  }
+}
+
+//One object for each pizza.
+class Pizza
+{
+  String ingredients;
+  //Number of ingredients.
+  int count;
+  int index = -1;
+}
+
+//One object for every delivery.
+class Delivery
+{
+  double cache[];
+  //Cache of previous values.
+  String ingredients = "";
+  //List of pizzas added.
+  String order_list = "";
+  //Number of ingredients.
+  int count;
+  //Current element count.
+  int c_orders;
+  //Total number of elements to be added.
+  int orders;
+  //Current high score.
+  double h_score;
+  //Current prospective addition.
+  int p_id;
+
+  Delivery(int t_orders)
+  {orders = t_orders;}
+
+  //Compute the score for a pizza.
+  //The greater the better.
+  double pizzaScore(Pizza p, int index)
+  {
+    if(cache[index] != 0)
+    {
+      if(cache[index] < h_score)
+      {return 0;}
+    }
+
+    //Ingredients found and not found.
+    int found = 0;
+    int n_found = 0;
+
+    String ings[] = p.ingredients.split(" ");
+    for(String ing : ings)
+    {
+      if(ingredients.indexOf(ing) != -1)
+      {found++;}
+      else
+      {n_found++;}
+    }
+    //Score to be returned.
+    double score = Math.pow(n_found, 1 - found / p.count / 2);
+    cache[index] = score;
+    //things to be added here.
+    return score;
+  }
+}