Can somebody check my codes?(Counting numbers)

[PureAwesomeness]

This program is about counting the number of digits that exist in a string
there is no compile error on it but there is an error in the logics that i cant find it. So can somebody have a look at it, if you cant tell me the direct answer then please give me some hints. Thanks

Here is my codes

public class OccurrenceString
      {
            public static void main (String[] args)
            {
                                     System.out.println("SSN is 343 32 4545 and ID is 434 34 4323");

				String SSNandID = "SSN is 343 32 4545 and ID is 434 34 4323";

				int[] countNum = count(SSNandID);

			

				//display count array
				for(int i=0; i < countNum.length; i++)
				{
					if(countNum[i] != 0)
                    System.out.println(i +" appears "+ countNum[i] + ((countNum[i]==1)?" times.":" times."));
				}
			}//end of main

	public static int[] count(String SSNandID)
	{
		int counts[] = new int[10];

		for(int i = 0; i< SSNandID.length(); i++)
		{
			if(Character.isDigit(SSNandID.charAt(i)))
			{

			counts[SSNandID.charAt(i)]++;
		    }
		}//end of for
		return counts;

	}//end of count method

	}//end of OccurrenceString

[azzaiel]

This line might cause arrayIndexOutofBoundsExeption

public static int[] count(String SSNandID)
	{
		[COLOR="Red"]int counts[] = new int[10];[/COLOR]

try this:

public static int[] count(String SSNandID)
	{
		[COLOR="Red"]int counts[] = new int[SSNandID.length()];[/COLOR]

[PureAwesomeness]

This line might cause arrayIndexOutofBoundsExeption

public static int[] count(String SSNandID)
	{
		[COLOR="Red"]int counts[] = new int[10];[/COLOR]

try this:

public static int[] count(String SSNandID)
	{
		[COLOR="Red"]int counts[] = new int[SSNandID.length()];[/COLOR]

i cant use that because that is the length of the string. i used 10 in that array becuase there i wanted the array starts from 0-9 and increment a number whenever a number exists in the SSNandID string. its like counting how many 1s,2s,3s...9s in that string.
Thank you for your respond

[azzaiel]

ok sorry

public static int[] count(String SSNandID)
	{
		int counts[] = new int[10];

		for(int i = 0; i< SSNandID.length(); i++)
		{
			if(Character.isDigit(SSNandID.charAt(i)))
			{

			counts[i]++;
		    }
		}//end of for
		return counts;

	}//end of count method

change that to this:

public static int[] count(String SSNandID) {
		int counts[] = new int[11];
		
		for (int i = 0; i < SSNandID.length(); i++) {
			
			if (Character.isDigit(SSNandID.charAt(i))) {
				final Character cNum = SSNandID.charAt(i);
				final String sNum = cNum.toString();
			    int num = Integer.parseInt(sNum);
			    counts[num] += 1;
			}
		}// end of for
		return counts;

	}

tell me if you have questions

[Eranga]

@OP: Much similar to the switch-case logic. If you can start from the basis logic, easy to find the solution. ;)

Just adding more..

Following is the switch-case logic

                switch(SSNandID.charAt(i)) {
                    case '0':
                        counts[0]++;
                        break;
                    case '1':
                        counts[1]++;
                        break;

No compare it with azzaiels' code. Doing the same thing in much much better way. :)

[PureAwesomeness]

Thanks guys i got it!!!

[azzaiel]

@Eranga

so your gona make a case from case'0' to case'10' and hard code the value of the index of the array hmmm hows that better?

[Eranga]

@Eranga

so your gona make a case from case'0' to case'10' and hard code the value of the index of the array hmmm hows that better?

No way, that's the bad way I can program the logic. What I'm trying to point there is, that's the basic logic and implementation we can follow. Very basis about the deal with multiple options.

I never advice to follow that way in any case.

[corlettk]

My humble 2c's worth...

package forums;

class FrequencyOfDigitsTest
{
  public static void main(String[] args) {
    try {
      System.out.println(java.util.Arrays.toString(frequencyOfDigits("0123456789012345")));
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  public static int[] frequencyOfDigits(String text) {
    int counts[] = new int[10];
    for ( char c : text.toCharArray() ) {
      if ( Character.isDigit(c) ) {
        counts[Integer.parseInt(String.valueOf(c))]++;
      }
    }
    return counts;
  }
}