# rotation-100pt [題目在這](https://play.picoctf.org/practice/challenge/373?originalEvent=72&page=2) ## 題意 ![](https://i.imgur.com/9AdsLhQ.png) ## 解題思路 給的檔案內容長這樣 ![](https://i.imgur.com/e7jNRkf.png) 括號前面很明顯是 picoCTF 字母往前推九位,用 Ceaser 長這樣,但是不對 ![](https://i.imgur.com/RSwIWgg.png) 將 {} 跟數字單獨出來不動,感覺就是這個了 OWO ![](https://i.imgur.com/sRhF9Qj.png) 下面是 code : ```python= text = "" result = "" s = 18 def ceaser(text): result = "" for i in range(len(text)): char = text[i] if (char.isupper()): result += chr((ord(char) + s - 65) % 26 + 65) elif (char.islower()): result += chr((ord(char) + s - 97) % 26 + 97) else: result += char print(result) text = input("What is your encode: ") ceaser(text) ``` ## 困難之處 nope Date : 2023/04/10 ###### tags: `picoCTF2023` [`從零開始的 picoCTF`](https://hackmd.io/-KQeDuzrQMOcFNhwU_5eKA?both=) `picoCTF` `Cryptography`