package Dec2016;  

import java.util.HashSet;  

public class Ques1205 {  

    public static void main(String[] args){  

        StringBuffer sb1 = new StringBuffer("123");

        StringBuffer sb2 = new StringBuffer("123");

        StringBuffer sb3 = new StringBuffer("123");

        StringBuffer sb4 = new StringBuffer("123");  

        HashSet<StringBuffer> set = new HashSet<StringBuffer>();

        set.add(sb1);

        set.add(sb2);

        set.add(sb3);

        set.add(sb4);  

        System.out.println(set.size());

    }

}