gistfile1.txt

public class Main {

	public static void main(String[] args) {
		int[][] arr = { { 0, 5 }, { 10, 25 }, { 30, 10 }, { 30, 5 }, { 299, 5 }, { 299, 1 } };
		try {
			new Engine(arr);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}

import java.util.LinkedList;
import java.util.List;

public class Engine {

	int[][] arr;
	final int MAX_TIME = 300;
	List<Customer> aList = new LinkedList<Customer>();

	int maxQueueSize = 0;
	int maxWaitTime = Integer.MIN_VALUE;
	int minWaitTime = Integer.MAX_VALUE;

	public Engine(int[][] arr) throws Exception {
		if (arr == null || arr.length == 0) {
			throw new Exception("Input data array cannot be null or empty!");
		}
		this.arr = arr;
		this.aList = new LinkedList<Customer>();
		this.execute();
		this.print();
	}

	private void execute() {
		int length = 0;
		for (int i = 0; i < MAX_TIME; i++) {
			System.out.println("At Time: " + i + " Length: " + length);
			while (length < arr.length && i == arr[length][0]) {
				Customer aCustomer = new Customer();
				aCustomer.qETime = arr[length][0];
				aCustomer.iWTime = arr[length][1];
				aCustomer.eWTime = 0;
				aCustomer.qWTime = 0;
				if (aCustomer.qETime + aCustomer.iWTime < MAX_TIME) {
					System.out.println("Adding .... " + aCustomer);
					aList.add(aCustomer);
				} else {
					System.out.println("Discarding ... [" + arr[length][0] + "," + arr[length][1] + "]");
				}
				length++;
				if (length >= arr.length) {
					break;
				}
			}

			int queueCount = 0;
			boolean flag = false;
			for (Customer c : aList) {
				if (i >= c.qETime && c.iWTime > 0 && !flag) {
					c.eWTime++;
					c.iWTime--;
					flag = true;
				} else if (c.iWTime > 0) {
					c.eWTime++;
					c.qWTime++;
				}
				if (c.iWTime > 0) {
					queueCount++;
				}
			}
			if (queueCount > maxQueueSize) {
				maxQueueSize = queueCount;
			}
			System.out.println(aList);
		}

		for (Customer c : aList) {
			if (c.qWTime > maxWaitTime) {
				maxWaitTime = c.qWTime;
			}
			if (c.qWTime < minWaitTime) {
				minWaitTime = c.qWTime;
			}
		}
	}

	public void print() {

		System.out.println("\n--------------------------- RESULT ----------------------------\n");
		System.out.println("Maximum queue size: " + maxQueueSize);
		System.out.println("Maximum wait time: " + maxWaitTime);
		System.out.println("Maximum wait time: " + minWaitTime);

	}
}

class Customer {
	// Queue Entry Time ...
	int qETime;
	// Initial Wait Time ...
	int iWTime;
	// Effective Wait Time ...
	int eWTime;
	// Queue Wait Time ...
	int qWTime;

	public String toString() {
		return "" + qETime + " : " + iWTime + " : " + eWTime + " : " + qWTime;
	}
}

Last few lines of the output ....

[0 : 0 : 5, 10 : 0 : 25, 30 : 0 : 15, 30 : 0 : 20]
At Time: 299 Length: 4
Discarding ... [299,5]
Discarding ... [299,1]
[0 : 0 : 5, 10 : 0 : 25, 30 : 0 : 15, 30 : 0 : 20]

--------------------------- RESULT ----------------------------

Maximum queue size: 3
Maximum wait time: 25
Maximum wait time: 5

Last few lines of the new output ....

[0 : 0 : 5 : 0, 10 : 0 : 25 : 0, 30 : 0 : 15 : 5, 30 : 0 : 20 : 15]
At Time: 299 Length: 4
Discarding ... [299,5]
Discarding ... [299,1]
[0 : 0 : 5 : 0, 10 : 0 : 25 : 0, 30 : 0 : 15 : 5, 30 : 0 : 20 : 15]

--------------------------- RESULT ----------------------------

Maximum queue size: 3
Maximum wait time: 15
Maximum wait time: 0