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: 6111 sottrazione 1219 aggiunta 1586 aggiunta 8642 sottrazione 9020 sottrazione 1187
A:
4913