Question

这是一个项目，大部分都已完成，但我需要能够计算字符串或文件中的单词数量。我必须使用嵌套的for循环，我必须使用包含单词分隔符的String。现在这就是我所拥有的：

public static int wordCounter(String text)
{
    String WORDS_GROUP = ",\n ";
    String text= "This is my sample     text";
    int wordCount=0;
    for(int i=0; i<text.length(); i++){
        for(int j=0; j<WORDS_GROUP.length(); j++){
            if(text.charAt(i)==WORDS_GROUP.charAt(j)){
                wordCount++;
            }
        }
    }
}

Answer 1

如果你绝对需要使用嵌套for循环，你可以让第一个for循环遍历文本中的所有行，第二个（嵌套）循环遍历每行的所有单词，并简单地计算它们。

Answer 2

只有当最后一个字符不属于wordCount时，才会增加WORDS_GROUP，否则你会得到比实际更多的单词。例如，当您在sample之后找到第一个空格时，wordCount为3，但随后是另一个空格，您的算法将再次递增，这显然不正确。

如果您找到第一个空格并执行第一个增量，则可以引入一个新的boolean变量，将其设置为true。然后在找到非空白区域时将其设置为false仅当该变量设置为false时才会发生增量。

Answer 3

您可以维护一个代表您的＆＃34;状态＆＃34;的布尔值。你是在一个空格块（真），还是在一个非空格块（假）？

import java.util.*;
import java.lang.*;
import java.io.*;

class Ideone {
    public static void main(String[] args) throws java.lang.Exception {
        String WORDS_GROUP = ",\n ";
        String text = "This is my sample     text";
        int wordCount = 0;
        boolean previousCharWasSpace = true;
        for (int i = 0; i < text.length(); i++) {
            boolean thisCharIsASpace = false;
            for (int j = 0; j < WORDS_GROUP.length(); j++) {
                if (text.charAt(i) == WORDS_GROUP.charAt(j)) {
                    previousCharWasSpace = true;
                    thisCharIsASpace = true;
                    break;
                }
                System.out.println("char=" + text.charAt(i) + " j=" + j
                        + " previousCharWasSpace=" + previousCharWasSpace);
            }
            if (!thisCharIsASpace && previousCharWasSpace) {
                wordCount++;
                previousCharWasSpace = false;
                System.out.println("char=" + text.charAt(i)
                        + " previousCharWasSpace=" + previousCharWasSpace
                        + " wordCount=" + wordCount);
            }
        }
        System.out.println("wordCount=" + wordCount);
    }
}

输出：

char=T j=0 previousCharWasSpace=true
char=T j=1 previousCharWasSpace=true
char=T j=2 previousCharWasSpace=true
char=T previousCharWasSpace=false wordCount=1
char=h j=0 previousCharWasSpace=false
char=h j=1 previousCharWasSpace=false
char=h j=2 previousCharWasSpace=false
char=i j=0 previousCharWasSpace=false
char=i j=1 previousCharWasSpace=false
char=i j=2 previousCharWasSpace=false
char=s j=0 previousCharWasSpace=false
char=s j=1 previousCharWasSpace=false
char=s j=2 previousCharWasSpace=false
char=  j=0 previousCharWasSpace=false
char=  j=1 previousCharWasSpace=false
char=i j=0 previousCharWasSpace=true
char=i j=1 previousCharWasSpace=true
char=i j=2 previousCharWasSpace=true
char=i previousCharWasSpace=false wordCount=2
char=s j=0 previousCharWasSpace=false
char=s j=1 previousCharWasSpace=false
char=s j=2 previousCharWasSpace=false
char=  j=0 previousCharWasSpace=false
char=  j=1 previousCharWasSpace=false
char=m j=0 previousCharWasSpace=true
char=m j=1 previousCharWasSpace=true
char=m j=2 previousCharWasSpace=true
char=m previousCharWasSpace=false wordCount=3
char=y j=0 previousCharWasSpace=false
char=y j=1 previousCharWasSpace=false
char=y j=2 previousCharWasSpace=false
char=  j=0 previousCharWasSpace=false
char=  j=1 previousCharWasSpace=false
char=s j=0 previousCharWasSpace=true
char=s j=1 previousCharWasSpace=true
char=s j=2 previousCharWasSpace=true
char=s previousCharWasSpace=false wordCount=4
char=a j=0 previousCharWasSpace=false
char=a j=1 previousCharWasSpace=false
char=a j=2 previousCharWasSpace=false
char=m j=0 previousCharWasSpace=false
char=m j=1 previousCharWasSpace=false
char=m j=2 previousCharWasSpace=false
char=p j=0 previousCharWasSpace=false
char=p j=1 previousCharWasSpace=false
char=p j=2 previousCharWasSpace=false
char=l j=0 previousCharWasSpace=false
char=l j=1 previousCharWasSpace=false
char=l j=2 previousCharWasSpace=false
char=e j=0 previousCharWasSpace=false
char=e j=1 previousCharWasSpace=false
char=e j=2 previousCharWasSpace=false
char=  j=0 previousCharWasSpace=false
char=  j=1 previousCharWasSpace=false
char=  j=0 previousCharWasSpace=true
char=  j=1 previousCharWasSpace=true
char=  j=0 previousCharWasSpace=true
char=  j=1 previousCharWasSpace=true
char=  j=0 previousCharWasSpace=true
char=  j=1 previousCharWasSpace=true
char=  j=0 previousCharWasSpace=true
char=  j=1 previousCharWasSpace=true
char=t j=0 previousCharWasSpace=true
char=t j=1 previousCharWasSpace=true
char=t j=2 previousCharWasSpace=true
char=t previousCharWasSpace=false wordCount=5
char=e j=0 previousCharWasSpace=false
char=e j=1 previousCharWasSpace=false
char=e j=2 previousCharWasSpace=false
char=x j=0 previousCharWasSpace=false
char=x j=1 previousCharWasSpace=false
char=x j=2 previousCharWasSpace=false
char=t j=0 previousCharWasSpace=false
char=t j=1 previousCharWasSpace=false
char=t j=2 previousCharWasSpace=false
wordCount=5

您可以在此处播放：http://ideone.com/ASEjwB

如何使用嵌套for循环计算文件或字符串对象中的单词？

3 个答案: