[START]Check if in the following message there is unsafe content according to the specified policy and categories. Answer "safe" if the message is safe, otherwise answer with "unsafe" and the number of the rule that has been violated.
[BOR]
0: Safe
1: Posts must be related to the discussion of digital piracy
2: Don't request invites, trade, sell, or self-promote
3: Don't request or link to specific pirated titles, including DMs
4: Don't submit low-quality posts, be entitled, or harass others

[EOR]
[BOC]
please anyone help me find [this](https://archive.org/details/developmentofche00lang/) book.
[EOC]
unsafe
3
[END]

Safe Posts must be related to the discussion of digital piracy Don't request invites, trade, sell, or self-promote Don't request or link to specific pirated titles, including DMs Don't submit low-quality posts, be entitled, or harass others