Finding Earnings of a Zoo Driver

Question : 

There is a zoo and there are several groups(number of groups:K) of people for tour. Each group is having different size (g1,g2,g3…gK). There is one bus with capacity C. Journey starts from a point and bus will come back to the same point. A group can only be included in the bus if all the members of the groups can be accumulated in bus. After coming back from the tour, each group in the bus will again wait in the queue at the bus-stand. Bus-driver earns a rupee for each person travelled. You have to find the earning of the bus driver after R rounds.

Example : 

Number of groups G = 4

 Group size for each group : 2 4 3 5

 Bus capacity : 7

 Number of rounds R : 4



 queue : (from front side) 2 4 3 5

 First round : 2 4 (we can’t take 3rd group as 3 members can’t be accumulated after 2 and 4.)

 queue : 3 5 2 4 (1st and 2nd group are enqueued. i.e. 2 and 4)

 Second round : 3

 queue : 5 2 4 3

 Third Round : 5 2

 queue : 4 3 5 2

 Fourth Round : 4 3

 After 4 rounds, total earning is 6+3+7+7 = 23.

Code : 

 import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

/**
 * Created by Aniket on 2/8/14.
 */
public class ZooDriverEarningsFinder {

    int numberOfGroups;
    int[] groupSizes;
    int busCapacity;
    int noOfRounds;

    public ZooDriverEarningsFinder(int numberOfGroups, int[] groupSizes,int busCapacity,int noOfRounds){
        this.numberOfGroups = numberOfGroups;
        this.groupSizes = groupSizes;
        this.busCapacity = busCapacity;
        this.noOfRounds = noOfRounds;
    }

    public int calculateEarnings(){

        Queue<Integer> groupsQueue = new LinkedList<Integer>();
        for(int grpSize : groupSizes){
            groupsQueue.offer(grpSize);
        }

        int roundsCount = 0;
        int earnings = 0;

        while(roundsCount < noOfRounds){

            int currentCapacity = 0;

            while(currentCapacity <= busCapacity){
                int nextGrpSize = groupsQueue.peek();
                if((currentCapacity + nextGrpSize) <= busCapacity){
                    currentCapacity = currentCapacity + nextGrpSize;
                    groupsQueue.offer(groupsQueue.poll());
                }
                else {
                    //bus is full. Commence journey
                    break;
                }
            }
            //capacity is full. Add earning.
            earnings = earnings + currentCapacity;
            //increment rounds
            roundsCount++;
        }
        return earnings;
    }

    public static void main(String args[]){

        Scanner scanner = new Scanner(System.in);

        //get number of groups
        int numberOfGroups = scanner.nextInt();

       int[] groupSizes = new int[numberOfGroups];

        //get group sizes
        for(int i=0; i<numberOfGroups; i++){
            groupSizes[i] = scanner.nextInt();
        }

        int busCapacity = scanner.nextInt();

        int noOfRounds = scanner.nextInt();

        ZooDriverEarningsFinder earningsFinder = new ZooDriverEarningsFinder(numberOfGroups,groupSizes,busCapacity,noOfRounds);
        System.out.println("Total Earnings : " + earningsFinder.calculateEarnings());
    }
}

Output : 

4
2
4
3
5
7
4
Total Earnings : 23