public class CountCharRecursive {
     public static int count(char[] arr,char chr){return count(arr,chr,arr.length-1);}

    public static int count(char[] arr,char chr,int idx){
    if(idx < 0){return 0;}
    if(arr[idx]==chr){return 1+count(arr,chr,idx-1);}
    return 0+count(arr,chr,idx-1);
    }

    public static void main(String[] args) {

      char[] test = {'A','B','A','C','D','A','F','A','F','B','C','A','D','A','a'};
      System.out.println(count(test, 'a'));
    }

}