Counting the number of occurences of characters in a string [duplicate]

Answer 1

I think what you are looking for is this:

public class Ques2 {

/**
 * @param args the command line arguments
 */
public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String input = br.readLine().toLowerCase();
    StringBuilder result = new StringBuilder();
    char currentCharacter;
    int count;

    for (int i = 0; i < input.length(); i++) {
        currentCharacter = input.charAt(i);
        count = 1;
        while (i < input.length() - 1 && input.charAt(i + 1) == currentCharacter) {
            count++;
            i++;
        }
        result.append(currentCharacter);
        result.append(count);
    }

    System.out.println("" + result);
}

}