01204212/codes/zooma

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First implemenation with arrays

FlexiArray.java

public class FlexiArray<T> {

	public interface ItemMatcher<T> {
		boolean isMatch(T item); 
	}
	
	private T[] items;
	private int itemCount;
	private int size;

	@SuppressWarnings("unchecked")
	public FlexiArray(int size) {
		this.items = (T[]) new Object[size];
		this.size = size;
		this.itemCount = 0;
	}
	
	public int findIndex(ItemMatcher<T> matcher) {
		for(int i=0; i<itemCount; i++) {
			if(matcher.isMatch(items[i])) {
				return i;
			}
		}
		return -1;
	}
	
	public void insert(int i, T item) {
		for(int j=itemCount - 1; j >= i; j--) {
			items[j + 1] = items[j];
		}
		items[i] = item;
		itemCount++;
	}

	public void remove(int i) {
		for(int j = i + 1; j < itemCount; j++) {
			items[j - 1] = items[j];
		}
		itemCount--;
	}
	
	public T get(int i) {
		return items[i];
	}
}

Examples of lambda expression

Using lambda expression:

			pLocation = outComments.findIndex((Comment c) -> (c.getId() == p));

Without lambda (anonymous class):

			pLocation = outComments.findIndex(new FlexiArray.ItemMatcher<Comment>() {
				public boolean isMatch(Comment c) {
					return c.getId() == p;
				}
			});

Zooma 1 solution with linked list (ListNode)

ListNode.java

public class ListNode {
	public int val;
	public ListNode next = null;
	
	public ListNode(int val) {
		this.val = val;
		this.next = null;
	}
	
	public ListNode() {
		this(0);
	}
}

Main.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
 
public class Main {
	private int n,m;
	private int[] c;
	private int[] d;
	private int[] p;
 
	public static void main(String[] args) throws IOException {
		Main main = new Main();
 
		main.process();
	}
 
	private void process() throws IOException {
	    readInput();
	    
	    ListNode[] nodes = new ListNode[n + m + 1];
	    
	    ListNode head = null;
	    ListNode tail = null;
	    
	    for(int i=0; i<n; i++) {
	    	ListNode newNode = new ListNode(i+1);
	    	nodes[i+1] = newNode; 
	    	
	    	if(tail != null) {
	    		tail.next = newNode;
	    		tail = newNode;
	    	} else {
	    		head = tail = newNode;
	    	}
	    }
	    
	    for(int i=0; i<m; i++) {
	    	int ballNumber = n + i + 1;
	    	int pred = p[i];
	    	
	    	ListNode newNode = new ListNode(ballNumber);
	    	nodes[ballNumber] = newNode;
	    	
	    	/* -----  this is the deleted code where we look for the node with val=pred
		    ListNode currentNode = head;
		    while(currentNode != null) {
		    	if(currentNode.val == pred) {
		    		break;
		    	}
		    	currentNode = currentNode.next;
		    }
	    	*/
	    	
	    	ListNode currentNode = nodes[pred];
	    	
		    newNode.next = currentNode.next;
		    currentNode.next = newNode;
	    }
	    
	    ListNode currentNode = head;
	    while(currentNode != null) {
	    	System.out.println(currentNode.val);
	    	currentNode = currentNode.next;
	    }
	}
 
	private void readInput() throws IOException {
	    BufferedReader reader = new BufferedReader(
	               new InputStreamReader(System.in) );
 
	    String[] items = reader.readLine().split(" "); 
		n = Integer.parseInt(items[0]);
		m = Integer.parseInt(items[1]);
 
		c = new int[n];
		d = new int[m];
		p = new int[m];
 
		for(int i=0; i<n; i++) {
			c[i] = Integer.parseInt(reader.readLine());
		}
 
		for(int j=0; j<m; j++) {
			items = reader.readLine().split(" ");
			d[j] = Integer.parseInt(items[0]);
			p[j] = Integer.parseInt(items[1]);
		}
	}
}