编写一个不使用数组查找第二长单词的程序

Question

I need a java program to find the second-longest word in a sentence (without using an array).

This is the code I have so far:

import java.io.*;
class Second_longest_Trial {
  public static void main(String args[]) throws IOException {
    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    System.out.println("Enter the sentence");
    String s = in .readLine();
    s = s.trim() + " ";
    String longest = s.substring(0, s.indexOf(' '));
    String sec = longest;
    int l = s.length();
    String temp = " ", str = " ";

    for (int i = s.indexOf(' ') + 1; i < l; i++) {
      char ch = s.charAt(i);

      if (ch != ' ')
        temp = temp + ch;
      else {
        if (temp.length() > longest.length()) {
          sec = longest;
          longest = temp;
        } else if (temp.length() > sec.length()) {
          sec = temp;
        }
        temp = " ";
      }
    }

    System.out.println("Longest word is " + longest);
    System.out.println("Second Longest word is " + sec);
  }
}

When I am giving the input-

Sayan goes home.

This outputs-

Longest word is Sayan Second Longest word is Sayan

I should have got the output as follows-

Longest word is Sayan Second Longest word is goes

Answer 1

Drop your wonky initial setting of longest and sec . Create them and temp the following way:

String longest="";
String sec="";
String temp="";

for(int i = 0; i < l; i++) {
    ...

Why would you set longest and sec both to the first word - guess what happens if that first word is the longest in the sentence?

Then your code produces the output:

Longest word is Sayan
Second Longest word is home.

That is more correct than what you currently have but still not what you would expect ... because there is the . at the end of the sentence you have to take care of - maybe make the check for ch!=' ' a bit more complex and check against '.' as well. I leave it for you to figure out how to do that correctly.

Answer 2

This is happening because you have initialized the longest element as first word and sec also as longest(which is Sayan itself). Now longest = "Sayan" and sec = "Sayan", you went inside the array but you never found any word which is bigger than longest or sec.

Answer 3

Here is a very basic code to find the second longest word:

       class Second
       {
            public static void main(String str)//str has the required sentence
            {
                String m="",q="";
                int lar=0;
                str=str+" ";
                for(int i=1;i<=2;i++)
                {
                    for(int k=0;k<str.length();k++)
                    {
                       char ch=str.charAt(k);
                       if(ch!=' ')
                       m=m+ch;
                       else
                       {
                           if(m.length()>lar)
                           {
                              q=m;
                              lar=q.length();
                           }
                           m="";
                       }
                     }
                     if(i==1)
                     {
                        System.out.println("The longest word is: "+q);
                        str=str.replace(q," ");
                        lar=0;
                     }
                }
                System.out.println("The second longest word is: "+q);
             }
       }