Assign words into an array from an input string-CodePudding

I have a task in where I am instructed to create a method that returns words from a string based on a given length. The specific instructions are as follows:

This method will input a sentence with multiple words separated by spaces. The input number represents the size of the word we are looking for. Return a string array with all words found with the input size

Example:

String s = “Monday is a new day”;
int n = 3; //3 letter words
howManyWord(s, n) returns {“new”, “day”}
howManyWord(s, 2) returns {“is”}.

So far, this is my take at the solution. The main issue I am having is in the second for loop in terms of assigning words to the array itself

public String[] howManyWord(String s, int n) {
        //count the amount of words in the String
        int counter1 = 0;
        for(int a1 = 1; a1 < s.length(); a1  ) {
          char c1 = s.charAt(a1-1);
          char c2 = s.charAt(a1);
          if(c1 != ' ' && c2 == ' '){
              counter1  ;
          }
        }

        counter1  = 1;
        //Get the words of a string into an array   the loop in question
        String[] words = new String[counter1];
        String[] output = new String[counter1];
        for(int a2 = 1; a2 < s.length(); a2  ) {
            char c1 = s.charAt(a2-1);
          char c2 = s.charAt(a2);
          int counter2 = 0;
          if(c1 != ' ' && c2 == ' '){
              int index1 = s.indexOf(c1);
              int index2 = s.indexOf(c2);
              words[counter2] = s.substring(index1, index2);
                  counter2  ;
          }
        }

        //assign words of a specific length into output array
        for(int a3 = 0; a3 < output.length; a3  ) {
           if(words[a3].length() == n){
               output[a3] = words[a3];
           }
        }
        return output;
        }

How would I go about this issue? Thanks!

CodePudding user response：

Yor code is to complicate. use:

public static longhowManyWord(String s, int n) {
    
    String[] words = s.split(" "); // split at blank to get all words
    return Arrays.stream(words).filter(s1 -> s1.length() == n).count(); // filter all words woth the length of n and count them
}

CodePudding user response：

Use split() to gets words from the sentence, stream them filtering for the length, then return the filtered words as an array:

public String[] findWords(String s, int wordLength) {
    return Arrays.stream(s.split(" "))
      .filter(word -> word.length() == wordLength)
      .toArray(String[]::new);
}

Also note the renaming of your method to findWords and the renaming of the parameter n to wordLength to be more descriptive; you're not returning how many (with return type int) but finding words with a certain length.