Hint 1

Since the value 3 was not deleted fro the list, the bug must be in method remove. Add a breakpoint at the first line of this method (where currentfront. It points to a node storing instance variable element of value 1; this node points to another node storing value 2, and so on.

Repeatedly click on "step over" or press F6 until the condition of the if statement inside the while loop is true. at this point variable current is pointing to the node storing the value 3 (check this in the "Variables" window of the debugger). Press F6 once again until the break statement is highlighted. At this point the value 3 must have been removed from the list. Check if this is the case: look at the value of variable front in the "Variables" window and follow the pointers of the nodes in the list referenced by front; is the node storing the value 3 still in the list?