惜字如金1Crypto 未解决
惜字如金一向是程序开发的优良传统。无论是「creat」还是「referer」,都无不闪耀着程序员「节约每句话中的每一个字母」的优秀品质。本届信息安全大赛组委会决定贯彻落实这一精神,首次面向公众发布了「惜字如金化」(XZRJification)标准规范,现将该标准介绍如下。
惜字如金化标准
惜字如金化指的是将一串文本中的部分字符删除,从而形成另一串文本的过程。该标准针对的是文本中所有由 52 个拉丁字母连续排布形成的序列,在下文中统称为「单词」。一个单词中除「AEIOUaeiou
」外的 42 个字母被称作「辅音字母」。整个惜字如金化的过程按照以下两条原则对文本中的每个单词进行操作:
- 第一原则(又称 creat 原则):如单词最后一个字母为「
e
」或「E
」,且该字母的上一个字母为辅音字母,则该字母予以删除。 - 第二原则(又称 referer 原则):如单词中存在一串全部由完全相同(忽略大小写)的辅音字母组成的子串,则该子串仅保留第一个字母。
容易证明惜字如金化操作是幂等的:惜字如金化多次和惜字如金化一次的结果相同。
你的任务
我们为你提供了两个文件签名任务,分别称作 HS384 和 RS384。在每个任务中成功完成 3 次签名即可拿到对应 FLAG。
我们还为你提供了两个脚本方便你完成这两个任务——当然,这两个脚本已经被分别惜字如金化过了。
附注
本文已经过惜字如金化处理。
XIZIRUJIN has always been a good tradition of programing. Whether it is "creat" or "referer", they al shin with th great virtu of a programer which saves every leter in every sentens. Th Hackergam 2022 Comitee decided to inherit this spirit, and released th specification of "XZRJification" standard to th public for th first tim. W now introduc th standard as folows.
XZRJification Standard
XZRJification refers to th proces of deleting som characters in a text which forms another text. Th standard aims at al th continuous sequences of 52 Latin leters named as "word"s in a text. Th 42 leters in a word except "AEIOUaeiou
" ar caled "consonant"s. Th XZRJification proces operates on each word in th text acording to th folowing two principles:
- Th first principl (also known as creat principl): If th last leter of th word is "
e
" or "E
", and th previous leter of this leter is a consonant, th leter wil b deleted. - Th second principl (also known as referer principl): If ther is a substring of th sam consonant (ignoring cas) in a word, only th first leter of th substring wil b reserved.
It is easy to prov that XZRJification is idempotent: th result of procesing XZRJification multipl times is exactly th sam as that of only onc.
Your Task
Ther ar two tasks named HS384 and RS384, which need you to generat signatures for files. Sucesfuly generating 3 signatures for each task wil lead you to th coresponding flag.
W also provid you with two scripts to help you complet thes two tasks - of cours, th two scripts hav been already procesed respectively through XZRJification.
Notes
This articl has been procesed through XZRJification.
补充说明 1:在本题中没有大写字母因「惜字如金化」而被删除。
No capital leters in this chaleng hav been deleted due to "XZRJification".
