Java. I want to repeat the words in the string, but something goes wrong in my code

Question

I want to repeat only the words in my input string. But the order of output is not right. Here's my code:

  public static String repeatWords(String s, int num){
    StringBuilder sb = new StringBuilder();
    StringBuilder sbtemporary = new StringBuilder();
    int leng = s.length();
    for (int i=0; i < leng; i++){
      char c = s.charAt(i);
      int b = (int) c;
      if (b >= 65 && b <= 90 || b >= 97 && b <= 122){
        sbtemporary.append(c);
      } else if (b == 32){
        sbtemporary.append(" ");
      }
      if (b == 32){
        for (int j = 1; j<= num-1; j++){
          sb = sb.append(" " + sbtemporary);
          sbtemporary.delete(0,sbtemporary.length());
        }
      }
      sb.append(c);
    }
    String str = sb.toString();
    return str;
  }

s is the input string, num is the times that needs to repeat. The result I want is like ：

  When the input is : "How are you? I am fine."  
  The output should be like: "How How are are you you?"

But the result of my code is:

"How How  are are  you? you  I I  am am  fine."

I don't really know where goes wrong, pls could someone help me with this?

zzzyfff · Answer 1 · 2021-10-12T03:27:46.197

0

    System.out.println((int) "?".charAt(0)); //63
    System.out.println((int) ".".charAt(0)); //46

"?" and "." do not append to sbtemporary.

edited Oct 12 '21 at 03:27

answered Oct 12 '21 at 03:22

zzzyfff

1
1

Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – Community Oct 12 '21 at 03:45

chanrlc · Answer 2 · 2021-10-12T03:47:15.510

Add this checking, and add to sbtemporary for the repeated part. System.out.println(repeatWords(str, 1));

if ( b == 63) {
    sb = sb.append(" " + sbtemporary);
    sb.append(c);
    break;  
}

if (b == 63) {                  
   for (int j = 1; j<= num; j++){
      sb.append(" " + sbtemporary);
   }

   sb.append(c);
    break;
}
 
public static String repeatWords(String s, int num) {
        StringBuilder sb = new StringBuilder();
        StringBuilder sbtemporary = new StringBuilder();
        int leng = s.length();

        for (int i = 0; i < leng; i++) {
            char c = s.charAt(i);
            int b = (int) c;

            if (b == 63) {                  
                for (int j = 1; j<= num; j++){
                   sb.append(" " + sbtemporary);
                }
                
                sb.append(c);
                break;
            }

            if (b >= 65 && b <= 90 || b >= 97 && b <= 122) {
                sbtemporary.append(c);
            } 

            if (b == 32 && sbtemporary.length() != 0){
                for (int j = 1; j<= num; j++){
                  sb.append(" " + sbtemporary);
                }
                sbtemporary.delete(0,sbtemporary.length());
              }
              sb.append(c);
        }

        String str = sb.toString();
        return str;
    }

score 0 · Answer 3 · answered Oct 12 '21 at 03:33

Corrected Code:-

public static String repeatWords(String s, int num){
    StringBuilder sb = new StringBuilder();
    StringBuilder sbtemporary = new StringBuilder();
    int leng = s.length();
    for (int i=0; i < leng; i++){
      char c = s.charAt(i);
      int b = (int) c;
      if (b >= 65 && b <= 90 || b >= 97 && b <= 122){
        sbtemporary.append(c);
      }
      if (b == 32 && sbtemporary.length() != 0){
        for (int j = 1; j<= num-1; j++){
          sb.append(" " + sbtemporary);
        }
        sbtemporary.delete(0,sbtemporary.length());
      }
      sb.append(c);
    }
    String str = sb.toString();
    return str;
  }

Changes:-

Removed the else if (b == 32) part where you are appending space to sbtemporary.
Delete content of sbtemporary outside the j loop, else it will work only for num == 2.
And in the if condition b == 32 added one more condition if sbtemporary is not empty.

score 0 · Answer 4 · answered Oct 12 '21 at 05:50

You can simply do this instead,

String content =  "How are you? I am fine.";
String[] words = content.split("\\s"); // `\\s` preserves any 2 or more repeated spaces

StringBuilder builder = new StringBuilder();
for(String word : words) {
    for(int i = 0; i < n; i++) { // n is the no. of times to repeat the word
        builder.append(word).append(" ");
    }
}

System.out.printf("Repeated String : %s", builder.toString().trim());

A more tidy way with Java8, here Collections.nCopies(n, word) simply returns you a list of the word repeated n times, which is converted in a single String separated by space, and eventually, all such repeated strings are converted in one finally resultant string separated by space.

String content =  "How are you? I am fine.";
String[] words = content.split("\\s");

String result = Arrays.stream(words)
                .map(word -> String.join(" ", Collections.nCopies(n, word)))
                .collect(Collectors.joining(" ")); //n is the no. of times to repeat the word
System.out.printf("Repeated String : %s", result);

Java. I want to repeat the words in the string, but something goes wrong in my code

4 Answers4