Operation Parser: Parse and Evaluate a Stream of Arithmetic Operations on Named Variables

Question

## Problem

You are given a list of operation strings, each in one of these formats:
- `"SET x 5"` -- assign value 5 to variable x
- `"ADD x y"` -- add variable y's value to variable x
- `"PRINT x"` -- output variable x's current value
- `"RESET x"` -- set variable x back to 0

Parse and execute the operations in order. Return a list of all PRINT outputs.

```python
def run_operations(ops: list[str]) -> list[int]:
    pass
```

**Example:**
```
ops = ["SET a 10", "SET b 5", "ADD a b", "PRINT a", "RESET b", "PRINT b"]
-> [15, 0]

ops = ["PRINT x"]  # x not set -> return 0 or raise?
```

## Follow-ups

1. How would you handle referencing an undefined variable -- return 0 (like a default dict), raise a `NameError`, or flag it?
2. Add a `MUL x y` operation. How does operator precedence matter (or not) in this interpreter model?
3. How would you extend this to support conditional operations: `"IF x > 0 THEN PRINT x"`?
4. If operations are streaming in real time (1 million ops/sec), what data structure and I/O approach keeps latency low?

Operation Parser: Parse and Evaluate a Stream of Arithmetic Operations on Named Variables

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