Teacher: In this task you will be given an arithmetic operation and you have to find its answer. The symbols of operators '+' and '-' has been swapped i.e you need to perform subtraction when you see a '+' symbol and  addition in case of '-' symbol.
Teacher: Now, understand the problem? If you are still confused, see the following example:
5 + 3
Solution: 2
Reason: Here, '+' represents subtraction operation. So, the answer is 2 (5-3=2).

Now, solve this instance: 4170 - 1679 - 3547
Student:
9396