Untitled

import java.util.ArrayList;
import java.util.HashSet;
import java.util.HashMap;
  
public class UserSolution {
  
    class Record{
        String[] value;
        boolean isDel;//Them vao de danh dau 1 ban ghi da bi xoa hay chua de khong phai xoa that trong hashmap
         
        public Record(String name, String number, String birthday, String email, String memo) {
            this.value = new String[5];
            this.value[0] = name;
            this.value[1] = number;
            this.value[2] = birthday;
            this.value[3] = email;
            this.value[4] = memo;
            this.isDel = false;
        }
    }
     
    HashMap<String, ArrayList<Record>>[] hmRecords;//5 hashmap luu cac ban ghi theo 5 truong gia tri
     
    public void InitDB() {
        hmRecords = new HashMap[5];
        for(int i=0; i<5; i++) {
            hmRecords[i] = new HashMap<>();
        }
    }
     
    public void Add(String name, String number, String birthday, String email, String memo) {
        Record newRecord = new Record(name, number, birthday, email, memo);//Tao 1 doi tuong ban ghi moi
        for(int i=0; i<5; i++) {
            ArrayList<Record> list = hmRecords[i].get(newRecord.value[i]);//Lay ra list trong hashmap
             
            if(list == null) {//Neu chua co list nao trong hashmap
                list = new ArrayList<>();
                hmRecords[i].put(newRecord.value[i], list);
            }
            list.add(newRecord);//Neu da co roi thi chi can them vao list hien tai
        }
    }
     
    public int Delete(int field, String str) {    
        int count = 0;
         
        ArrayList<Record> list = hmRecords[field].get(str);//Lay ra list tu truong thong tin trong hashmap tuong ung
        if(list != null) {
            for(Record record : list) {
                if(record.isDel == false) {
                    record.isDel = true;//Chi can danh dau ban ghi da bi xoa ma khong can xoa trong hashmap
                    count++;
                }
            }
        }
        return count;
    }
     
    public int Change(int field, String str, int changefield, String changestr) {
        Record newRecord = null;
        int count = 0;
        ArrayList<Record> listRecord = hmRecords[field].get(str);
        if(listRecord != null) {
            int size = listRecord.size();
            for(int i=0; i<size; i++) {
                Record rc = listRecord.get(i);
                if(rc.isDel == false) {
                    newRecord = rc;
                    rc.isDel = true;
                    newRecord.value[changefield] = changestr;
                    count++;
                    Add(newRecord.value[0], newRecord.value[1], newRecord.value[2], newRecord.value[3], newRecord.value[4]);//Them ban ghi voi gia tri moi vao hashmap
                }
            }
        }
        return count;
    }
     
    public Solution.Result Search(int field, String str, int returnfield) {
        Solution.Result s = new Solution.Result();
        s.count = 0;
        s.str = "";
         
        ArrayList<Record> listRecord = hmRecords[field].get(str);
        if(listRecord != null) {
            for(Record record : listRecord) {
				if(record.isDel == false) {
                    s.count++;
                    s.str = record.value[returnfield];
                }
            }
        }
         
        if(s.count > 1)
            s.str = "";
        return s;
    }
  
}