In this task you will be given an arithmetic operation in Italian and you have to find its answer. The operations 'addition' and 'subtraction' have been replaced with their italian translations i.e you need to perform addition when you see 'aggiunta' and subtraction in case of 'sottrazione'.

Example input: 10 sottrazione 7
Example output: 3
Example explanation: Here, 'sottrazione' represents the subtraction operation. So, the answer is 3 (10-7=3).
Q: 1408 aggiunta 6170 sottrazione 2421 aggiunta 591 aggiunta 864 aggiunta 2630 aggiunta 1563 aggiunta 4303 aggiunta 5509
A:
20617