Given are two strings, input string and a mask string that remove all the characters of the mask string from the original string.

Example:
INPUT:
ORIGINAL STRING: communication
MASK STRING: mont
OUTPUT: cuicai

A class StringOp is defined as follows to perform above operation.

Some of the members of the class are given below:
Class name: StringOp
Data members/instance variables:
str: to store the original string
msk: to store the mask string
nstr: to store the resultant string
Methods/Member functions:
StringOp(): default constructor to initialize the data members with legal initial values
void accept(): to accept the original string str and the mask string msk in lowercase
void form(): to form the new string nstr after removal of characters present in mask string from the original string.
void display(): to display the original string nstr and the newly formed string nstr

Specify the class StringOp giving details of the constructor, void accept(), void form() and void display(). Define a main() function to create an object and call all the functions accordingly to enable the task.

import java.util.Scanner;
class StringOp{
    String str;
    String msk;
    String nstr;
    public StringOp(){
        str = new String();
        msk = new String();
        nstr = new String();
    }
    public void accept(){
        Scanner in = new Scanner(System.in);
        System.out.print("ORIGINAL STRING: ");
        str = in.nextLine().toLowerCase();
        System.out.print("MASK STRING: ");
        msk = in.nextLine().toLowerCase();
    }
    public void form(){
        for(int i = 0; i < str.length(); i++){
            char ch = str.charAt(i);
            if(msk.indexOf(ch) == -1)
                nstr += ch;
        }
    }
    public void display(){
        System.out.println("ORIGINAL STRING: " + str);
        System.out.println("NEWLY FORMED STRING: " + nstr);
    }
    public static void main(String[] args){
        StringOp obj = new StringOp();
        obj.accept();
        obj.form();
        obj.display();
    }
}