public static String caesarCipher(String input, int k) {
// Write your code here
String iString="abcdefghijklmnopqrstuvwxyz";

//String shuffString=iString.substring(k, iString.length())+iString.substring(0, k);

k=k%26;

String outstring=""; String shuffString=iString.substring(k, iString.length())+iString.substring(0, k);

     for(int j=0;j<input.length();j++){
        for(int i=0;i<iString.length();i++){
                        if(Pattern.matches("[-_!@#$%^&*.]+",  String.valueOf(input.charAt(j)))==true) {
            outstring+=input.charAt(j) ; 
                break;
           }

            char tchar='\0';
            if(Character.isUpperCase(input.charAt(j))==true){
               tchar= Character.toLowerCase(input.charAt(j));
               if((tchar==iString.charAt(i))){

                outstring+=   Character.toUpperCase(shuffString.charAt(i));
               }

            }

            if( (input.charAt(j)==iString.charAt(i))) {

            outstring+=shuffString.charAt(i);
            break;
           }

     }
    }
   return outstring;

}