DiffK - facebook code lab - Your solution is not well optimized for runtime.

DiffK1.java

public class Solution {
	public int diffPossible(List<Integer> a, int b) {
	    if(a == null || a.size() == 0) 
	        return 0; 
	  
	    int sum = a.get(0).intValue() + b; 
	    int pos = getPos(a, sum); 
	    if(pos < a.size() && a.get(pos) == sum)
	        return 1; 
	    for(int i=1; i< a.size() && pos < a.size(); i++)
	    {
	        int tmpSum = a.get(i).intValue() + b; 
	        
	         
	        for(int j= pos; j< a.size(); j++)
	        {
	            int tmp2 = a.get(j).intValue(); 
	            if(tmp2 == tmpSum)
	                return 1; 
	            else if(tmp2 < tmpSum)
	                continue; 
	            else{
	                pos = j; 
	                break; 
	            }
	        }
	    }
	    
	    return 0; 
	}
	
	public int getPos(List<Integer> a, int sum)
	{
	    int len = a.size(); 
	    
	    int start = 0; 
	    int end = len -1; 
	    
	    if(sum > a.get(end).intValue() || sum < a.get(start).intValue())
	        return len;
	        
	    while(start < end)
	    {
	        int mid = (start + end)/ 2; 
	        int tmp = a.get(mid).intValue(); 
	        if(tmp == sum)
	            return mid; 
	        else if(tmp < sum)
	          start = mid; 
	        else 
	          end = mid; 
	    }
	    
	    return start; 
	}
	
	
}