Thread: help with string and counts

hi

i need help with exercise, i have a string: "aabbbacddd".

i need to run on that string and return evey set of letters like this:
'a' 2; 'b' 3; 'a' 1; 'c' 1...;

the trick part is when a letter returns again in the string after different letter.
in the first code it returns value 1,1,1 i need 3.

please help.

i tried writing all sort of stuff but didnwt get the answer.

    public int countLetters(char letter, String s)
    {
        int length = s.length()-1; //using the string object method length
        int value = 0; //initialize value integer to store the list value
 
        for(int i = 0; i <= length; i++) //moving along all the characters in the string
        {
            value = 1; //first, each char is get it own value(1)
            if(i < length && s.charAt(i)==s.charAt(i+1))
            //if the char equals the next char -
            {
                value++; //add +1 to value
                i++; //move to the next char
            }
        }
        return value;
    }

    public static int countLetter(char c, String s)
    {
        int value = 0;
        int length = s.length()-1;
 
        for(int i = 0; i <= length; i++)
        {
            if(s.charAt(i) == c)
            {
               value++;
            }
        }
        return value;
    }

10x

Welcome to the forum! Thanks for taking the time to learn how to post code correctly. If you haven't already, please read this topic to learn other useful info for new members.

An interesting characteristic of chars can be used here to create a character frequency counter using an array of ints and incrementing the char's corresponding array element. You can consult an ASCII chart to verify that the ASCII value for 'a' = 97. You can also create a short program to show that:

System.out.println( 'a' - 97 );

Will print '0' (zero). You can use those characteristics plus an array of 26 ints to count how many characters occur in a string. Incrementing the correct element of the frequency counter will look something like:

counter[input.charAt( i ) - 97]++;

Good luck!

hi

10q for the quick respond.
i found the solution, it was a bit more complicated because it's linked list exercise, and i've changed the thinking of all this.

again 10q very much.