共计 1826 个字符，预计需要花费 5 分钟才能阅读完成。
1. 题目 International Morse Code defines a standard encoding where each letter is mapped to a series of dots and dashes, as follows: “a” maps to “.-“, “b” maps to “-…”, “c” maps to “-.-.”, and so on.
For convenience, the full table for the 26 letters of the English alphabet is given below:
[“.-“,”-…”,”-.-.”,”-..”,”.”,”..-.”,”–.”,”….”,”..”,”.—“,”-.-“,”.-..”,”–“,”-.”,”—“,”.–.”,”–.-“,”.-.”,”…”,”-“,”..-“,”…-“,”.–“,”-..-“,”-.–“,”–..”]
Now, given a list of words, each word can be written as a concatenation of the Morse code of each letter. For example, “cba” can be written as “-.-..–…”, (which is the concatenation “-.-.” + “-…” + “.-“). We’ll call such a concatenation, the transformation of a word.
Return the number of different transformations among all words we have.
Example:
Input: words = [“gin”, “zen”, “gig”, “msg”]
Output: 2
Explanation:
The transformation of each word is:
“gin” -> “–…-.”
“zen” -> “–…-.”
“gig” -> “–…–.”
“msg” -> “–…–.”
There are 2 different transformations, “–…-.” and “–…–.”.
自己的解决方法
class Solution:
def uniqueMorseRepresentations(self, words: List[str]) -> int:
final_set = set()
mosLIst = [“.-“,”-…”,”-.-.”,”-..”,”.”,”..-.”,”–.”,”….”,”..”,”.—“,”-.-“,”.-..”,”–“,”-.”,”—“,”.–.”,”–.-“,”.-.”,”…”,”-“,”..-“,”…-“,”.–“,”-..-“,”-.–“,”–..”]
for word in words:
temp = ”
for i in word:
temp += mosLIst[ord(i)-97]
final_set.add(temp)
return len(final_set)
Runtime: 36 ms, faster than 97.45% of Python3 online submissions for Unique Morse Code Words.
Memory Usage: 12.9 MB, less than 5.36% of Python3 online submissions for Unique Morse Code Words.
3. 其他解决方法
const codes = [“.-“,”-…”,”-.-.”,”-..”,”.”,”..-.”,”–.”,”….”,”..”,”.—“,”-.-“,”.-..”,”–“,”-.”,”—“,”.–.”,”–.-“,”.-.”,”…”,”-“,”..-“,”…-“,”.–“,”-..-“,”-.–“,”–..”]
const getIdx = char => char.charCodeAt(0) – ‘a’.charCodeAt(0)
var uniqueMorseRepresentations = function(words) {
return words.map(word => word.split(”)
.map(char => codes[getIdx(char)])
.join(”))
.reduce((set, cur) => set.add(cur), new Set())
.size
};
