public static int charFrequency(String theString, char theChar){
        String str =theString;
        String m= str.toLowerCase();
        char g=theChar;
        char[] ch = m.toCharArray();

        int sum=0;

        for(char c: ch)
        {
            if (c==g){
                sum+=1;
            }

        }

        System.out.println(sum);

   return sum;
    }
