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Thread: Help with String based program!!!

  1. #1
    Junior Member astroann's Avatar
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    Unhappy Help with String based program!!!

    The Question is:
    Write a program to input a string and print the frequency of each character.
    Example:
    INPUT: COMPUTER HARDWARE
    OUTPUT: CHARACTERS FREQUENCY
    A 2
    C 1
    AND SO ON...
    The source code i wrote was:

    import java.io.*;
    class CharCount
    {
    public static void main(String args[])throws IOException
    {
    int i,h,k;
    String a="AZazAz^_^";
    int v=a.length();
    System.out.println("Character"+"\t"+"FREQUENCY");
    System.out.println(v);//here*
    for(i=65;i<123;i++)
    {h=0;
    for(k=0;k<v;k++)
    {
    if (a.charAt(k)==i)
    h++;
    }
    System.out.println(a.charAt(k) + "\t" + h);}}//#

    }

    There were no compilation errors.
    But when i ran it, the program executed till *.

    And the following errors came up:
    java.lang.StringIndexOutOfBoundsException: String index out of range:9
    at java.lang.String.charAt(String.java:686)
    at CharCount.main(CharCount.java.18)

    and the source code opened up with error in line #.

    Can some please help me with this. I m really stuck up. Urgent help neccesary. Thanks in advance.


  2. #2
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    Default Re: Help with String based program!!!

    here's my implementation.
    import java.io.*;
    class CharCount
    {
        public static void main(String args[]) throws IOException
        {
            int i,h,k;
            String a="bcDedAZazAz^_^";
            int v=a.length();
            char[] toChar = a.toLowerCase().toCharArray(); //get string to char array
            char[] charStore = new char[ v ]; // store characters found
            int [] charCountStore = new int[ v ]; //store count of characters found
            for(i=0;i<v;i++) { charCountStore[i]=0;} //initialize count to 0
            System.out.println("Character"+"\t"+"FREQUENCY");
            for(i=0;i< v; i++){
                if ( isInArray( charStore ,toChar[i] ) ){
                    for(h=0;h<v;h++){
                        if ( Character.valueOf( charStore[h]).equals(toChar[i]) ){
                            // increase count if found in the charStore array
                            charCountStore[h]++;
                        }
                    }
                }else{
                    charStore[i] = toChar[i];
                    charCountStore[i]++;
                }
            }
            for(i=0;i<v;i++){
                System.out.printf("%c\t\t%d\n", charStore[i],charCountStore[i] );
            }
        }
     
        public static boolean isInArray ( char[] a , char c){
            // check if character is in array, if yes, return true
            boolean found=false;
            for(int i=0;i< a.length; i++){
                if ( Character.valueOf(a[i]).equals(c) ){
                    found=true;
                    break;
                }
            }
            return found;
        }
     
    }

  3. The Following User Says Thank You to JavaHater For This Useful Post:

    astroann (December 27th, 2010)

  4. #3
    Junior Member astroann's Avatar
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    Smile Re: Help with String based program!!!

    import java.io.*;
    class CharCount
    {
    public static void main(String args[])throws IOException
    {
    int i,h,k;
    String a="AZazAz^_^";
    int v=a.length();
    System.out.println("Character"+"\t"+"FREQUENCY");
    System.out.println(v);//*
    for(i=65;i<123;i++)
    {h=0;
    for(k=0;k<v;k++)
    {
    if (a.charAt(k)==i)
    h++;
    }
    System.out.println(a.charAt(k-1) + "\t" + h);}}//#

    }

    The correction was at line # itself.
    I neede to write a.chatAt(k-1).
    It was because when a loop executes, then the iteration is executed, so at that time 'k' was 9, which did not exist.
    Thats all folks!!!

    Thanks @JavaHater.

  5. #4
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    Default Re: Help with String based program!!!

    Glad to see your problem was fixed, in the future please use the tags highlight=Java and [/highlight].
    ohai, java?

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