反转句子的每个第二个单词

Question

我正在尝试反转每个句子的第二个单词

如果给定的字符串是：

My name is xyz

所需的输出应为：

My eman is zyx

我当前的输出是：

Ym eman s1 zyx

我无法达到所需的输出。不知道我在做什么错

这是我的代码

    char[] sentence = "  Hi my name is person!".toCharArray();
    System.out.println(ReverseSentence(sentence));

}
private static char[] ReverseSentence(char[] sentence)
{
    //Given: "Hi my name is person!"
    //produce: "iH ym eman si !nosrep"

    if(sentence == null) return null;
    if(sentence.length == 1) return sentence;

    int startPosition=0;
    int counter = 0;
    int sentenceLength = sentence.length-1;

    //Solution handles any amount of spaces before, between words etc...

    while(counter <= sentenceLength)
    {
        if(sentence[counter] == ' ' && startPosition != -1 || sentenceLength == counter) //Have passed over a word so upon encountering a space or end of string reverse word
        {
            //swap from startPos to counter - 1
            //set start position to -1 and increment counter
            int begin = startPosition;

            int end;
            if(sentenceLength == counter)
            {
                end = counter;
            }
            else
                end = counter -1;
            char tmp;

            //Reverse characters
            while(end >= begin){

                tmp = sentence[begin];
                sentence[begin] = sentence[end];
                sentence[end] = tmp;

                end--; begin++;

            }

            startPosition = -1; //flag used to indicate we have no encountered a character of a string


        }

        else if(sentence[counter] !=' ' && startPosition == -1) //first time you encounter a letter in a word set the start position
        {
            startPosition = counter;
        }

        counter++;
    }

    return sentence;
}

Answer 1

您可以解决各种问题的简便方法！只需使用一个flag将指示 偶数 或 奇数 位置的变量，更准确地说是任何单词都将被反转！

查看我在您的代码中进行的以下修改，仅添加了三行：

private static boolean flag = true;// added a variable flag to check if we reverse the word or not.
private static char[] ReverseSentence(char[] sentence)
{
    //Given: "Hi my name is person!"
    //produce: "iH ym eman si !nosrep"

    if(sentence == null) return null;
    if(sentence.length == 1) return sentence;

    int startPosition=0;
    int counter = 0;
    int sentenceLength = sentence.length-1;

    //Solution handles any amount of spaces before, between words etc...

    while(counter <= sentenceLength)
    {
        if(sentence[counter] == ' ' && startPosition != -1 || sentenceLength == counter) //Have passed over a word so upon encountering a space or end of string reverse word
        {
            flag = !flag; // first time (odd position) we are not going to reverse!
            //swap from startPos to counter - 1
            //set start position to -1 and increment counter
            int begin = startPosition;

            int end;
            if(sentenceLength == counter)
            {
                end = counter;
            }
            else
                end = counter -1;
            char tmp;

            //Reverse characters
            while(end >= begin & flag){ //lets see whether we are going to reverse or not

                tmp = sentence[begin];
                sentence[begin] = sentence[end];
                sentence[end] = tmp;

                end--; begin++;

            }

            startPosition = -1; //flag used to indicate we have no encountered a character of a string


        }

        else if(sentence[counter] !=' ' && startPosition == -1) //first time you encounter a letter in a word set the start position
        {
            startPosition = counter;
        }

        counter++;
    }

    return sentence;
}

输入项

我叫xyz

输出：

我的eman是zyx