Design a mini compiler/interpreter
Company: Applied
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: easy
Interview Round: Onsite
## Problem
Design and implement a **mini compiler / interpreter** for a small expression language.
You are given a program as a string (possibly multiple lines). The language supports:
- Integer literals, e.g. `42`
- Variables and assignment, e.g. `x = 3 + 4`
- Arithmetic: `+ - * /` with standard precedence and parentheses
- Unary minus, e.g. `-x`
- A `print(expr)` statement that outputs an integer
### Task
Build a pipeline that:
1. Tokenizes the input (lexer)
2. Parses tokens into an AST (parser)
3. Evaluates the AST (interpreter) and produces the printed outputs in order
### Clarifications
- Integer division truncates toward zero.
- All variables are global.
- Invalid syntax should raise a clear error.
### Example
Program:
```
x = 10
print(x + 2 * 3)
print(-(x - 7))
```
Output:
```
16
-3
```
Quick Answer: This question evaluates understanding of language design and implementation skills, including lexical analysis, parsing into an AST, expression evaluation with operator precedence and unary operators, variable assignment semantics, and runtime error reporting.