2325 - Decode the Message.

Easy

You are given the strings key and message, which represent a cipher key and a secret message, respectively. The steps to decode message are as follows:

• Use the first appearance of all 26 lowercase English letters in key as the order of the substitution table.

• Align the substitution table with the regular English alphabet.

• Each letter in message is then substituted using the table.

• Spaces ' ' are transformed to themselves.

• For example, given <code>key = "<ins> hap </ins>p<ins> y </ins> <ins> bo </ins>y"</code> (actual key would have at least one instance of each letter in the alphabet), we have the partial substitution table of ('h' -> 'a', 'a' -> 'b', 'p' -> 'c', 'y' -> 'd', 'b' -> 'e', 'o' -> 'f').

Return the decoded message.

Example 1:

Input: key = "the quick brown fox jumps over the lazy dog", message = "vkbs bs t suepuv"

Output: "this is a secret"

Explanation: The diagram above shows the substitution table.

It is obtained by taking the first appearance of each letter in "<ins> the </ins> <ins> quick </ins> <ins> brown </ins> <ins> f </ins>o<ins> x </ins> <ins> j </ins>u<ins> mps </ins> o<ins> v </ins>er the <ins> lazy </ins> <ins> d </ins>o<ins> g </ins>".

Example 2:

Input: key = "eljuxhpwnyrdgtqkviszcfmabo", message = "zwx hnfx lqantp mnoeius ycgk vcnjrdb"

Output: "the five boxing wizards jump quickly"

Explanation: The diagram above shows the substitution table.

It is obtained by taking the first appearance of each letter in "<ins> eljuxhpwnyrdgtqkviszcfmabo </ins>".

Constraints:

• 26 <= key.length <= 2000

• key consists of lowercase English letters and ' '.

• key contains every letter in the English alphabet ('a' to 'z') at least once.

• 1 <= message.length <= 2000

• message consists of lowercase English letters and ' '.