LeetCode 2325. Decode the Message
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?
key = "happy?boy"
?(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 "the quick brown fox jumps over the lazy dog".
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 "eljuxhpwnyrdgtqkviszcfmabo".
?
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?' '
.題目是easy題目,其實(shí)就是做一個(gè)映射,然后根據(jù)message 返回映射的信息即可;
用hashmap可以,也可以直接用數(shù)組;下面是代碼:
Runtime:?7 ms, faster than?71.47%?of?Java?online submissions for?Decode the Message.
Memory Usage:?42.7 MB, less than?50.31%?of?Java?online submissions for?Decode the Message.