160_Intersection of Two Linked Lists

/*
160. Intersection of Two Linked Lists
Runtime: 1 ms, faster than 99.36% of Java online submissions for Intersection of Two Linked Lists.
Memory Usage: 52.9 MB, less than 22.73% of Java online submissions for Intersection of Two Linked Lists.

 */
public class Solution {
    public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
        ListNode test1=headA;
        ListNode test2=headB;
        if(headA==null || headB==null)
            return null;
        
        int l1=0,l2=0;
        while(test1!=null)
        {
            test1=test1.next;
            l1++;
        }
        while(test2!=null)
        {
            test2=test2.next;
            l2++;
        }
        
    test1=headA;
    test2=headB;
    int diff=Math.abs(l1-l2);
        
        if(l1>l2)
            while(diff!=0)
            {
                test1=test1.next;
                diff--;
            }
        
        if(l2>l1)
            while(diff!=0)
            {
                test2=test2.next;
                diff--;
            }
                
        
        while(test1!=null || test2!=null)
        {
            if(test1==test2)
                return test1;
            
            test1=test1.next;
            test2=test2.next;
            
        }
        
        return null;
    }
}