PHP returns notice about offset while the offset is OK
===

Please look at this code:  

    1. foreach($last_array as $item) {
    2.    	echo ($item[1] .'-'. $item[2]); 
    3.    	if ($item[1] != '' && $item[2]) {
    4.             ...

Now, imagine that `$last_array` contains **Val1** and **Val2**. In line 2 I can the output: 

> Val1 - Val2

But in line 3, I get this notice:

> Notice: Undefined offset: 1 in ...   
> Notice: Undefined offset: 2 in ...

What do you think? What is worng here ?  
If the offsets have any problem, how can I see their values?