CareerCup

I assume by "less than k value" you mean "less than or equal", due to your given outputs.

Anyways, here goes:

import java.util.*;

public class Test1{
	public static void main(String[] args){
		Scanner in = new Scanner(System.in);
		System.out.println("Length: ");
		int len = in.nextInt();
		int[] a = new int[len];
		for(int i = 0; i<len; i++){
			System.out.println("Element " + i + ": ");
			a[i] = in.nextInt();
		}
		System.out.println("Max sum: ");
		System.out.println(maximumLength(a,in.nextInt()));	
	}
	
	public static int maximumLength(int[]a, int k){
		PriorityQueue<Integer> heap = new PriorityQueue<Integer>();
		for(int item: a){
			heap.add(item);
		}	
		int sum = 0;
		int numElements = 0;
		while(sum <= k && !heap.isEmpty()){
			int item = heap.poll();	
			System.out.println("Polled " + item);	
			if(sum + item <= k){
				sum+= item;
				numElements++;
			}
			else{
				break;			
			}
		}
		return numElements;
	}
}

import java.util.*;

public class Test1{
	public static void main(String[] args){
		Scanner in = new Scanner(System.in);
		System.out.println("Length: ");
		int len = in.nextInt();
		int[] a = new int[len];
		for(int i = 0; i<len; i++){
			System.out.println("Element " + i + ": ");
			a[i] = in.nextInt();
		}
		System.out.println("Max sum: ");
		System.out.println(maximumLength(a,in.nextInt()));	
	}
	
	public static int maximumLength(int[]a, int k){
		PriorityQueue<Integer> heap = new PriorityQueue<Integer>();
		for(int item: a){
			heap.add(item);
		}	
		int sum = 0;
		int numElements = 0;
		while(sum <= k && !heap.isEmpty()){
			int item = heap.poll();	
			System.out.println("Polled " + item);	
			if(sum + item <= k){
				sum+= item;
				numElements++;
			}
			else{
				break;			
			}
		}
		return numElements;
	}
}

static int maximumLength(int[] a, int k) { 
  int sum = 0;
  for(int i=0; i<a.size(); ++i) {
    if (sum+a[i] < k) {
      sum +=a[i];  
    }
  }
  return sum;
}

static int maximumLength(int[] a, int k) { 
  int sum = 0;
  for(int i = 0; i < sizeof(a)/sizeof(a[i]); ++i)  {
    if (sum + a[i] < k)  {
      sum += a[i];
    }
  }  
  return sum;
}

your question is not clear