Goal
You are given an ordered collection of signs to interpret as an assembly language, which you need to execute to obtain a number.
The language assumes a simple integer register of unlimited size, although results will never go beyond 16-bit signed number capacity in practice. This register is set to 0, and operations apply to it to obtain a final value.
Instructions are executed from left to right, ignoring operator precedence. For example, /$$*?//// corresponds to ADD 3 followed by SUB 0, meaning the final result of the program is 0 + 3 - 0 = 3.
Available instructions are the following:
ADD N (/$, N characters, /)
Add N to the register, e.g. /$+-^/ is "ADD 3".
SUB N (//, N characters, /)
Substract N from the register, e.g. //+^+-$/ is "SUB 5".
MUL N + 1 (/**, N characters, /)
Multiply N + 1 and the register, e.g. /****/ is "MUL 3" (2 + 1).
MUL -N (/*/, N characters, /)
Multiply -N and the register, e.g. /*/**/ is "MUL -2".
ADD INST COUNT ($)
This instruction can have two meanings:
* If not counting, start counting the number of instructions from 0.
* Otherwise, add the number of counted instructions to the register and stop counting.
Note that the $ instruction itself is not counted.
For example, $/$$$$///./$ to add 3, substract 1 then add 2 (number of instructions: ADD 3, SUB 1).
NOP (/*$)
Do nothing.
All of the provided programs will be valid.
Input
First line: program to execute.
Output
First line: Result.
Constraints
0 < length(program) < 512
-32768 <= any register value <= 32767
