LeetCode 824 Goat Latin

LeetCode 824 Goat Latin

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题目分析

A sentence S is given, composed of words separated by spaces. Each word consists of lowercase and uppercase letters only.

We would like to convert the sentence to “Goat Latin” (a made-up language similar to Pig Latin.)

The rules of Goat Latin are as follows:

• If a word begins with a vowel (a, e, i, o, or u), append "ma" to the end of the word.
  For example, the word ‘apple’ becomes ‘applema’.
• If a word begins with a consonant (i.e. not a vowel), remove the first letter and append it to the end, then add "ma".
  For example, the word "goat" becomes "oatgma".
• Add one letter 'a' to the end of each word per its word index in the sentence, starting with 1.
  For example, the first word gets "a" added to the end, the second word gets "aa" added to the end and so on.

Return the final sentence representing the conversion from S to Goat Latin.

Example 1:

Input: "I speak Goat Latin"
Output: "Imaa peaksmaaa oatGmaaaa atinLmaaaaa"

Example 2:

Input: "The quick brown fox jumped over the lazy dog"
Output: "heTmaa uickqmaaa rownbmaaaa oxfmaaaaa umpedjmaaaaaa overmaaaaaaa hetmaaaaaaaa azylmaaaaaaaaa ogdmaaaaaaaaaa"

Notes:

• S contains only uppercase, lowercase and spaces. Exactly one space between each word.
• 1 <= S.length <= 100.

题义分析：给定一个字符串，转换为Goat Latin格式，转换规则如下：

1. 如果单词以元音开头，直接在单词后添加ma即可。
2. 如果单词不以原因开头，先将第一个字母移到单词最后面，添加ma即可。
3. 从第一个单词开始，都要加上若干个a的后缀，第一个单词加一个，第二个单词加两个等。

思考

直接按照题意给定的方法处理字符串即可。

代码实现

class Solution {
    public String toGoatLatin(String S) {
        StringBuilder sb = new StringBuilder();
        String[] words = S.split(" ");
        char[] map = new char[256];
        map['A'] = map['E'] = map['I'] = map['O'] = map['U'] =  1;
        map['a'] = map['e'] = map['i'] = map['o'] = map['u'] =  1;
        StringBuilder as = new StringBuilder("a");
        for (int i = 0; i < words.length; ++i) {
            // AEIOUaeiou
            if (map[words[i].charAt(0)] == 1) {
                sb.append(words[i]).append("ma");
            } else {
                sb.append(words[i].substring(1)).append(words[i].charAt(0)).append("ma");
            }
            sb.append(as);
            as.append("a");
            if (i != words.length - 1) {
                sb.append(" ");
            }
        }

        return sb.toString();
    }
}

感想

略