Add subtract and multiply

Let $x$ be a variable initially equals to $0$. Simulate the next operations with this variable:

• add $a$: add value $a$ to $x$;

• subtract $a$: subtract value $a$ from $x$;

• multiply $a$: multiply $x$ by $a$;

Input

Each line contains operation and value. Process all given operations. The value of the variable $x$ after each operation doen not exceed $10^9$ by absolute value.

Output

Print the resulting value of $x$.

Examples