Leetcode 804 Unique Morse Code Words

Unique Morse code word

1. C++ practice

class Solution {
public:
    int uniqueMorseRepresentations(vector<string>& words) {
        string morse[]={".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."};
        set<string> res;
        for(int i=0;i<words.size();i++){
            string tmp="";
            string cur=words[i];
            for(int j=0;j<cur.length();j++){
                tmp+=morse[cur[j]-'a'];//'a' is 97 'z' is 122 Convert the character number to the numeric number b-'a' is 98-97=1 a-'a ' is 97-97=0
            }
            res.insert(tmp);
        }
        return res.size();//Map deduplication
    }
};

2.java practice

class Solution {
    public int uniqueMorseRepresentations(String[] words) {
        String[] morseCode= {".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."};  
        HashSet<String> set=new HashSet<>();
        for(String word:words){//String in java should be capitalized
            String code="";
            for(char c:word.toCharArray())//toCharArray() converts a string to a character array
                code +=morseCode[c-'a'];
            set.add(code);
        }
        return set.size();//According to HashSet, duplicate elements cannot be placed
    }
}

toCharArray() method

3. python practice

class Solution:  
    def uniqueMorseRepresentations(self, words):  
          
        d = [".-","-...","-.-.","-..",".","..-.","--.","....","..",".---","-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-","..-","...-",".--","-..-","-.--","--.."]  
          
        return len({''.join(d [ord(i)-ord('a')]for i in w) for w in words})  

Whether you can read it or not, it feels a little clear, so write it down first and learn python well