如何统计文本文件中唯一词的个数？不允许使用哈希

Question

我需要创建一个程序来计算文件中的单词数量和唯一单词的数量……我已经想出了如何计算单词的数量，但我在计算唯一单词部分时遇到了麻烦。这是我的统计总字数的方法。

public static int numberWord(File f) throws FileNotFoundException{
    Scanner welcome = new Scanner(f);
    int count=0;
    while(welcome.hasNext()){
        String word=welcome.next();
        count++;
    }
    return count;

Answer 1

嗯，这是一项荒谬的任务，而且通常是一种糟糕的实现任务的方式。

无论如何，这里有一些伪代码和一个简单的方法定义，可以用来解决任务-它有可怕的复杂性界限和固定的限制，但它应该足以开始一个。

// Find the index of the word within an array.
// If the word currently is not in the array, then
// add it and return the index the word was added at.
int ensureWord(String[] words, String word) {
    for each index in words do
        if the word is equal() to the word at the index then
            // existing word found
            return the index
        if (null) is at the index then
            // "found the end" of the known words, so must be a new word
            assign word to the words array at the index
            return the index

    throw terrible exception, word not ensured
}

String words[] = new String[MAX_DISTINCT_WORDS_ALLOWED];
String counts[] = new int[MAX_DISTINCT_WORDS_ALLOWED];

for each word in the file do
   find/ensure the index in words by invoking ensureWord(words, word)
   and increment the count at the index by one