public void pre_in_to_post(){
		
		int inIndex = 0;
		LinkedList<String> leftSide = null;
		LinkedList<String> rightSide = null;
		
		if(pre.size() % 2 == 1 && pre.size() == in.size()
							   && pre.peekLast() == in.peekLast()){
			String preIndex = pre.getFirst();
			
			for(int i = 0; i < in.size(); i++){
				if(in.get(i) == preIndex){
					inIndex = i;
				}
			}
			
			for(int j = 0; j < inIndex; j++){
				leftSide.add(in.get(j));
			}
			
			for(int k = inIndex + 1; k < in.size(); k++){
				rightSide.add(in.get(k));
			}
			
			
			
		}
		else{
			System.out.println("bad input: no full tree has these preorder and inorder traversals");
		}
	}