class CountOccurrences {
  public static void main(String[] args) throws java.lang.Exception {
    printOccurrences("AAAABBCCCDAA");
  }
 
  public static void printOccurrences(String str) {
    int len = str.length();
    char[] arr = str.toCharArray();
    char contChar = arr[0];
    int count = 0;
    StringBuffer sb = new StringBuffer();
    for (int i = 0; i < arr.length; i++) {
      if (contChar == arr[i]) {
        count++;
        if (i + 1 >= arr.length) {
          sb.append(count).append(contChar);
        }
      } else {
        sb.append(count).append(contChar);
        contChar = arr[i];
        count = 0;
        i--;
      }
    }
    System.out.println(sb.toString());
  }
}
 

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