java - 使用 for 循环从带计数的句子中找到重复的单词

Question

由于我是 Java 的新手，我的任务是仅查找重复的单词及其计数。我卡在一个地方，无法获得适当的输出。我不能使用任何集合和内置工具。我试过下面的代码。需要一些帮助，请帮帮我。

public class RepeatedWord 
  {
   public static void main(String[] args) 
      {
          String sen = "hi hello hi good morning hello";
          String word[] = sen.split(" ");
          int count=0;
          for( int i=0;i<word.length;i++)
             {
                for( int j=0;j<word.length;j++)
                   {
                       if(word[i].equals(word[j]))
                          {
                             count++;
                          }
                         if(count>1)
                   System.out.println("the word "+word[i]+" occured"+ count+" time");
                   }

             }

       }
 }

期望输出:-

the word hi occured 2 time
the word hello occured 2 time

但我得到如下输出:-

the word hi occured 2 time
the word hi occured 2 time
the word hi occured 2 time
the word hi occured 2 time
the word hello occured 2 time
the word hi occured 2 time
the word hi occured 2 time
the word hi occured 2 time
the word hi occured 2 time
the word hello occured 2 time

请帮我得到我期望的输出。并请解释。这样我也能理解。 提前致谢

Answer 1

您只需要为外层循环打印结果。此外，您需要避免检查在上一次迭代中已经检查过的单词:

for (int i = 0; i < word.length; i++) {
    int count = 0; // reset the counter for each word

    for (int j = 0; j < word.length; j++) {

        if (word[i].equals(word[j])) {
            /* if the words are the same, but j < i, it was already calculated
               and printed earlier, so we can stop checking the current word
               and move on to another one */
            if (j < i) {
                break; // exit the inner loop, continue with the outer one
            }

            count++;
        }
    }

    if (count > 1) {
        System.out.println("the word " + word[i] + " occured " + count + " time");
    }
}

更新

关于此代码的附加说明:if (j < i) { break; }

i是我们计算重复的单词的索引，j是我们比较它的词。因为我们总是从头开始，所以我们知道如果 j < i 的单词相等, 它已经在外循环的早期运行中处理过。

在这种情况下，使用 break ，我们中断内循环，流程在外循环中继续。因为我们没有更新 count根本上，它仍然是零，因此是打印结果的条件 if (count > 1)不满意，println不执行。

单词“hello”的示例，在以下部分使用简单的伪代码。

第一次出现:

count = 0
    i = 1, j = 0 --> hello != hi                  --> do nothing
    i = 1, j = 1 --> hello == hello, j is not < i --> count++
    i = 1, j = 2 --> hello != hi                  --> do nothing
    i = 1, j = 3 --> hello != good                --> do nothing
    i = 1, j = 4 --> hello != morning             --> do nothing
    i = 1, j = 5 --> hello == hello, j is not < i --> count++
count > 1        --> print the result

第二次出现:

count = 0
    i = 5, j = 0 --> hello != hi           --> do nothing
    i = 5, j = 1 --> hello == hello, j < i --> break, we have seen this pair earlier
count is not > 1 --> result not printed

希望这个例子没有让事情变得更复杂