识别信号
- Do you handle subtractive notation like IV and IX correctly?
- Can you explain how your hash table mapping covers all decimal place values?
- Do you understand how the subtraction rule works in Roman numerals?
解题流程
- 1. 明确窗口/状态定义
- 2. 更新状态并维护约束
- 3. 用边界样例验证
常见失分点
- Ignoring subtractive combinations, leading to outputs like IIII instead of IV.
- Misunderstanding the subtraction rule, such as treating 'IV' as 'IIII' or incorrectly handling cases like 'IX'.
- Failing to correctly identify the repeating decimal pattern.
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