#t125. 凯撒密码

凯撒密码

Caesar Cipher

Problem Description

The Caesar cipher is a substitution cipher in which every letter in the plaintext is shifted a fixed number of positions forward (or backward) in the alphabet and replaced by the corresponding letter in the ciphertext. For example, when the shift is 33, every letter A is replaced by D, B by E, C by F, and so on; W is replaced by Z, X by A, Y by B, Z by C. This encryption method is named after Julius Caesar, the Roman general, who is said to have used it to communicate with his generals.

But like all substitution ciphers based on the alphabet, the Caesar cipher is very easy to break, and it cannot guarantee communication security in practice.

Now you are given a cracked Caesar-cipher plaintext and its ciphertext, together with an uncracked Caesar-cipher ciphertext that uses the same shift. Please help crack it.

Input Format

The input consists of three lines:

  • The first line contains a string, the cracked Caesar-cipher plaintext;
  • The second line contains a string, the Caesar-cipher ciphertext corresponding to the first line;
  • The third line contains a string, the Caesar-cipher ciphertext to be cracked.

Output Format

Output one line containing a string: the plaintext corresponding to the ciphertext to be cracked.

Sample Input

ABCDEFGVWXYZ
DEFGHIJYZABC
WKHTXLFNEURZQIRAMXPSVRYHUWKHODCBGRJ

Sample Output

THEQUICKBROWNFOXJUMPSOVERTHELAZYDOG

Sample Explanation

From the first line of plaintext ABCDEFGVWXYZ and the second line of ciphertext DEFGHIJYZABC we can compute that the shift is 33 (for example, the letter A becomes D, and D is 33 positions after A in the alphabet). Therefore, applying the same reverse shift (i.e. moving each letter backward by 33 positions) to the third line's ciphertext to be cracked: W moves back 33 positions to become T, K moves back 33 to become H, and so on, finally yielding the plaintext THEQUICKBROWNFOXJUMPSOVERTHELAZYDOG.

Constraints

The lengths of all strings do not exceed 10001000, and all strings consist of uppercase letters.