diff --git a/admin_user.h b/admin_user.h
index 8c45f21..43f0963 100644
--- a/admin_user.h
+++ b/admin_user.h
@@ -120,89 +120,80 @@ int admin_menu_user_choices(char* name,char* role){
 
 //invetory control
 void add_item();
-void remove_item();
-void update_item();
-void view_item();
+void remove_item(struct inventory db,int index);
+void update_item(struct inventory db,int index);
 void admin_list_pages(struct inventory db);
+void item_control(struct inventory db,int index);
 
-void inv_control(){
+int prompt_inv_control(){
+    int choice = 0;
+    do{
         system("cls");
-        struct inventory db = read_db_invt();
-        admin_list_pages(db,NULL,db.row);
+        printf("Please select an option:\n");
+        printf("1. List(allow all operation include add)\n");
+        printf("2. Add item(shortcut to add item)\n");
+        printf("3. Exit\n");
+        printf(">");
+        scanf("%d", &choice);
+        if(choice < 1 || choice > 3){
+            printf("Invalid choice...press any key to retry....\n");
+            fflush(stdin);
+            getchar();
+        }
+    }while(choice < 1 || choice > 3);
+    return choice;
 }
 
-void item_control(struct inventory db,int index);
-void admin_list_pages(struct inventory db,struct Map* map,int row){//user for showing list result and search result
-    int choice = -1;
-    int page = 0;
-    int page_size = PAGE_SIZE;
-    int total_pages = ceil((double)row / page_size);
-    do{
-
-    //options
-    system("cls");
-    printf("0 exit\n");
-    printf("1 sort name decending\n");
-    printf("2 sort name ascending\n");
-    printf("3 sort price decending\n");
-    printf("4 sort price ascending\n");
-    printf("5 sort brand decending\n");
-    printf("6 sort brand ascending\n");
-    printf("7 sort category decending\n");
-    printf("8 sort category ascending\n");
-    printf("List of items:\n");
-
-    //print items
-    if(page + 1 >= total_pages){
-        print_page(db, page * page_size, row,map);
-    }else{//sorted)
-        print_page(db, page * page_size, (page + 1) * page_size,map);
-    }
-    printf("%d new item",page_size+4);
-    //page control
-    printf("%d next page\n", page_size+5);
-    printf("%d previous page\n", page_size+6);
-    printf("%d set page size\n", page_size+7);
-    printf("%d/%d/%d(page size/page number/total)\n",page_size, page+1,total_pages);
-
-    //prompt user to select an item
-    bool valid = true; 
-    do{
-        valid = true;
-        printf("Enter your choice: ");
-        fflush(stdin);
-        scanf("%d", &choice);
-        if(choice <=8 && choice > 0){
-            printf("sorting...\n");
-            map = sortItems(db,choice);
-        }else if(choice == page_size+3){
-            add_item();
-        }else if(choice == page_size+4 && page + 1 < total_pages){
-            page++;
-        }else if(choice == page_size+5 && page > 0){
-            page--;
-        }else if(choice == page_size+6){
-            printf("Enter page size: ");
-            fflush(stdin);
-            scanf("%d", &page_size);
-            total_pages = ceil(row / page_size);
-        }else if(choice >= 9 && choice < row+9){
-            item_control(db,choice - 9 + page_size*page);   
-        }else if(choice != 0){
-            printf("Invalid choice\n");
-            valid = false;
+void inv_control(){
+        struct inventory db = read_db_invt();
+        int choice = 0;
+        do{
+        choice = prompt_inv_control();
+        switch (choice){
+            case 1://list
+                //add a new element with product name new item
+                //for item control
+                db.row = (struct inventory_row *)realloc(db.row, sizeof(struct inventory_row) * (db.db.row_count + 1));
+                db.db.row_count += 1;
+                strcpy(db.row[db.db.row_count - 1].product,"CREATE NEW ITEM");
+                db.row[db.db.row_count - 1].barcode = -1024;//IMPORTANT: -1024 is reserved for new item
+                list_page(db,NULL,db.db.row_count,item_control);
+                break;
+            case 2://add item
+                add_item();
+                break;
+            case 3://exit
+                break;
+            default://should not happen
+                printf("Invalid choice\n");
+                break;
         }
-    }while(!valid);
+        }while(choice != 3);
+}
 
-    }while(choice != 0);
+void show_item_admin(struct inventory db,int index){
+    system("cls");
+    printf("Product: %s\n", db.row[index].product);
+    printf("Catergory: %s\n", db.row[index].category);
+    printf("Brand: %s\n", db.row[index].brand);
+    printf("Price: $%lf\n", db.row[index].price);
+    printf("Stock: %d\n", db.row[index].stock);
+    printf("Barcode: %ld\n",db.row[index].barcode);
+    getchar();
+    return;
 }
 
 void item_control(struct inventory db,int index){
     int choice = 0;
+    if(db.row[index].barcode == -1024){//new item
+        add_item();
+        return;
+    }
     do
     {
         system("cls");
-        show_item(db,index);
+        show_item_admin(db,index);
+        printf("Operations\n");
         printf("0 exit\n");
         printf("1 update item\n");
         printf("2 remove item\n");
@@ -223,26 +214,65 @@ void item_control(struct inventory db,int index){
     } while (choice != 0);
 }
 
+char* prompt_item(char* prompt){
+    char* item = malloc(sizeof(char) * 100);
+    do{
+        printf("%s",prompt);
+        fflush(stdin);
+        scanf("%[^\n]",item);
+        if(strcmp(item,"") == 0){
+            printf("Invalid input, try again?(y/n)\n");
+            fflush(stdin);
+            char c = getchar(); 
+            if(c == 'n'){
+                return NULL;
+            }
+        }
+    }while(strcmp(item,"") == 0);
+    return item;
+}
+
 void add_item(){
+    char* temp;
     system("cls");
     printf("Add new item\n");
-    printf("Please input the item name\n>");
-    struct inventory_row *item;
-    fflush(stdin);
-    scanf("%[^\n]", item->product);
-    printf("Please input the item brand\n>");
-    fflush(stdin);
-    scanf("%[^\n]", item->brand);
-    printf("Please input the item price\n>");
-    scanf("%lf", &item->price);
-    printf("Please input the item stock\n>");
-    scanf("%d", &item->stock);
-    printf("Please input the item category\n>");
-    fflush(stdin);
-    scanf("%[^\n]", item->category);
-    printf("Please input the item barcode\n>");
-    fflush(stdin);
-    scanf("%[^\n]", item->barcode);
+    struct inventory_row *item = (struct inventory_row *)malloc(sizeof(struct inventory_row));
+    temp = prompt_item("Please input the name: \n>");
+    if(temp == NULL){
+        free(item);
+        return;
+    }
+    strcpy(item->product,temp);
+    temp = prompt_item("Please input the brand: \n>");
+    if(temp == NULL){
+        free(item);
+        return;
+    }
+    strcpy(item->brand,temp);
+    temp = prompt_item("Please input the category: \n>");
+    if(temp == NULL){
+        free(item);
+        return;
+    }
+    strcpy(item->category,temp);
+    temp = prompt_item("Please input the price: \n>");
+    if(temp == NULL){
+        free(item);
+        return;
+    }
+    item->price = atof(temp);
+    temp = prompt_item("Please input the stock: \n>");
+    if(temp == NULL){
+        free(item);
+        return;
+    }
+    item->stock = atoi(temp);
+    temp = prompt_item("Please input the barcode: \n>");
+    if(temp == NULL){
+        free(item);
+        return;
+    }
+    item->barcode = atol(temp);
     if(item == NULL || !append_inventory(item)){
         printf("Failed to add item\n");
     }else{
@@ -254,24 +284,52 @@ void add_item(){
 }
 
 void update_item(struct inventory db,int index){
-    system("cls");
-    printf("Update item\n");
-    printf("Please input the item name\n>");
+    char temp[100];
+    printf("Update item(empty value to not change the value)\n");
+    
+    printf("Please input the name(original:%s)\n>",db.row[index].product);
     fflush(stdin);
-    scanf("%[^\n]", db.row[index].product);
-    printf("Please input the item brand\n>");
+    scanf("%[^\n]", temp);//input until /n
+    if(strcmp(temp,"") != 0){//check if temp is not empty
+        strcpy(db.row[index].product,temp);//if yes, copy temp to product
+    }//else preserve the original value
+    
+    printf("Please input the brand(orginal:%s)\n>",db.row[index].brand);
     fflush(stdin);
-    scanf("%[^\n]", db.row[index].brand);
-    printf("Please input the item price\n>");
-    scanf("%lf", &db.row[index].price);
-    printf("Please input the item stock\n>");
-    scanf("%d", &db.row[index].stock);
-    printf("Please input the item category\n>");
+    scanf("%[^\n]", temp);
+    if(strcmp(temp,"") != 0){
+        strcpy(db.row[index].brand,temp);
+    }
+    
+    printf("Please input the category(orginal:%s)\n>",db.row[index].category);
     fflush(stdin);
-    scanf("%[^\n]", db.row[index].category);
-    printf("Please input the item barcode\n>");
+    scanf("%[^\n]", temp);
+    if(strcmp(temp,"") != 0){
+        strcpy(db.row[index].category,temp);
+    }
+    
+    printf("Please input the price(orginal:$%.1lf)\n>",db.row[index].price);
     fflush(stdin);
-    scanf("%[^\n]", db.row[index].barcode);
+    scanf("%[^\n]", temp);
+    if(strcmp(temp,"") != 0){
+        db.row[index].price = atof(temp);
+    }
+    
+    printf("Please input the stock(orginal:%d)\n>",db.row[index].stock);
+    fflush(stdin);
+    scanf("%[^\n]", temp);
+    if(strcmp(temp,"") != 0){
+        db.row[index].stock = atoi(temp);
+    }
+
+    printf("Please input the barcode(original:%ld)\n>",db.row[index].barcode);
+    fflush(stdin);
+    scanf("%[^\n]", temp);
+    if(strcmp(temp,"") != 0){
+        db.row[index].barcode = atol(temp);
+    }
+
+
     if(!update_db_invt(db)){
         printf("Failed to update item\n");
     }else{
@@ -283,7 +341,6 @@ void update_item(struct inventory db,int index){
 }
 
 void remove_item(struct inventory db,int index){
-    system("cls");
     printf("Remove item\n");
     printf("Are you sure you want to remove this item? (y/n)\n");
     char choice;
diff --git a/data_file_admin.txt b/data_file_admin.txt
index 2f31a47..1b3a9ee 100644
--- a/data_file_admin.txt
+++ b/data_file_admin.txt
@@ -1,4 +1,4 @@
 #name of role that are consider as admin
-Teacher
+teacher
 Staff
 Admin
\ No newline at end of file
diff --git a/database.h b/database.h
index b2bb15b..f49d02f 100644
--- a/database.h
+++ b/database.h
@@ -15,7 +15,7 @@
 #endif // !DNT_H
 typedef struct basic_db{
     int row_count;
-    bool init_status;
+    bool init_status;//not really used can be useful
     //array of struct of row
 }basic_db;
 
@@ -298,6 +298,8 @@ bool update_db_invt(struct inventory invt){
         return false;
     }
     for(int i=0;i<invt.db.row_count;i++){
+        if(invt.row[i].barcode == -1024)//skip create new row
+            continue;
         if(invt.row[i].isdeleted == true){
             continue;
         }
@@ -451,29 +453,12 @@ bool append_inventory(struct inventory_row* row){
         printf("Error in opening file\n");
         return false;
     }
-    for(INVENTORY i=category;i<=ENDOFINVENTORY;i++){
-        switch(i){
-            case category:
-                fprintf(fp,"%s",row.category);
-                break;
-            case brand:
-                fprintf(fp,"%s",row.brand);
-                break;
-            case product:
-                fprintf(fp,"%s",row.product);
-                break;
-            case price_inv:
-                fprintf(fp,"%.1f",row.price);
-                break;
-            case stock:
-                fprintf(fp,"%d",row.stock);
-                break;
-            case barcode_inv:
-                fprintf(fp,"%ld",row.barcode);
-                break;
-        }
-        fprintf(fp,"\n");
-    }
+    fprintf(fp,"%s\n",row->category);
+    fprintf(fp,"%s\n",row->brand);
+    fprintf(fp,"%s\n",row->product);
+    fprintf(fp,"%.1f\n",row->price);
+    fprintf(fp,"%d\n",row->stock);
+    fprintf(fp,"%ld\n",row->barcode);
     fclose(fp);
     return true;
 }
@@ -484,29 +469,12 @@ bool append_transaction_db(struct transaction_row* row){
         printf("Error in opening file\n");
         return false;
     }
-    for(TRANSACTION i=date;i<=ENDOFTRANSACTION;i++){
-        switch(i){
-            case date:
-                fprintf(fp,"%d-%02d-%02d",row.date.year,row.date.month,row.date.day);
-                break;
-            case TIME:
-                fprintf(fp,"%02d:%02d:%02d",row.time.hour,row.time.minute,row.time.second);
-                break;
-            case id_tran:
-                fprintf(fp,"%ld",row.id);
-                break;
-            case price_tran:
-                fprintf(fp,"%.1f",row.price);
-                break;
-            case quantity:
-                fprintf(fp,"%d",row.quantity);
-                break;
-            case barcode_tran:
-                fprintf(fp,"%ld",row.barcode);
-                break;
-        }
-        fprintf(fp,"\n");
-    }
+    fprintf(fp,"%d-%02d-%02d\n",row->date.year,row->date.month,row->date.day);
+    fprintf(fp,"%02d:%02d:%02d\n",row->time.hour,row->time.minute,row->time.second);
+    fprintf(fp,"%ld\n",row->id);
+    fprintf(fp,"%.1f\n",row->price);
+    fprintf(fp,"%d\n",row->quantity);
+    fprintf(fp,"%ld\n",row->barcode);
     fclose(fp);
     return true;
 }
@@ -517,20 +485,9 @@ bool append_user(struct user_row* row){
         printf("Error in opening file\n");
         return false;
     }
-    for(USER i=name;i<=ENDOFUSER;i++){
-        switch(i){
-            case name:
-                fprintf(fp,"%s",row.name);
-                break;
-            case role:
-                fprintf(fp,"%s",row.role);
-                break;
-            case id_user:
-                fprintf(fp,"%ld",row.id);
-                break;
-        }
-        fprintf(fp,"\n");
-    }
+    fprintf(fp,"%s\n",row->name);
+    fprintf(fp,"%s\n",row->role);
+    fprintf(fp,"%ld\n",row->id);
     fclose(fp);
     return true;
 }
diff --git a/normal_user.h b/normal_user.h
index f9af3fc..b6b1035 100644
--- a/normal_user.h
+++ b/normal_user.h
@@ -85,7 +85,9 @@ int normal_menu_user_choices(){
     scanf("%d", &choice);
     return choice;
 }
-void list_page(struct inventory db,struct Map* map,int row){//user for showing list result and search result
+
+//user for showing list result and search result
+void list_page(struct inventory db,struct Map* map,int row,void (*showitem)(struct inventory,int)){//showitem is a function pointer for showing item,allow customization for better flexibilty  
     int choice = -1;
     int page = 0;
     int page_size = PAGE_SIZE;
@@ -138,7 +140,7 @@ void list_page(struct inventory db,struct Map* map,int row){//user for showing l
             scanf("%d", &page_size);
             total_pages = ceil(row / page_size);
         }else if(choice >= 9 && choice < row+9){
-            show_item(db,choice - 9 + page_size*page);   
+            (*showitem)(db,choice - 9 + page_size*page);
         }else if(choice != 0){
             printf("Invalid choice\n");
             valid = false;
@@ -172,7 +174,7 @@ void list_items(){
     
     struct inventory db = read_db_invt();
     struct Map* map = NULL;
-    list_page(db,map,db.db.row_count);
+    list_page(db,map,db.db.row_count,show_item);
 }
 
 //for sorting
@@ -180,6 +182,9 @@ struct Map* sortItems(struct inventory db, int sort){
     struct Map *map = malloc(sizeof(struct Map) * db.db.row_count);
     for (int i = 0; i < db.db.row_count; i++){
         map[i].key = i;
+        if(db.row[i].barcode == -1024)//catch new item
+            map[i].value = NULL;
+
         switch(sort){
             case 1:
             case 2:
@@ -259,7 +264,7 @@ void search_item(){
     printf("searching...\n");
     map = searchItems(db,searchstr);
     if(map[0].value > 0){
-        list_page(db,map+1,(int)map[0].value);//ofset map, as it is use to store the size
+        list_page(db,map+1,(int)map[0].value,show_item);//ofset map, as it is use to store the size
     }else{//empty search
         printf("No result found\n");
         printf("Press any key to continue\n");
@@ -479,7 +484,7 @@ struct cart* scan_barcode(struct cart* cart,struct inventory db){
         do{
             system("cls");    
             printf("product: %s\n",row->product);
-            printf("price: %.2f\n",row->price);
+            printf("price: %.1f\n",row->price);
             printf("Enter quantity(0 to cancel)\n>");\
             fflush(stdin);
             scanf("%d", &quantity);
@@ -556,15 +561,15 @@ struct cart* list_cart(struct cart* cart){
                 double price = temp->row->price * qty;
                 total_price += price;
                 printf("%d product:%s\n",i,temp->row->product);
-                printf("  price(per qty): %.2f\n",temp->row->price);//space to align
-                printf("  price(total): %.2f\n",price);
+                printf("  price(per qty): %.1f\n",temp->row->price);//space to align
+                printf("  price(total): %.1f\n",price);
                 printf("  quantity: %d\n",qty);
                 printf("<------------------------>\n");
                 temp = temp->next;
                 i++;
             }
             printf("\n<------------------------>\n");
-            printf("Total price: $%.2f\n",total_price);
+            printf("Total price: $%.1f\n",total_price);
             printf("<------------------------>\n");
 
             printf("\n%d CHECKOUT\n",i);
@@ -595,7 +600,7 @@ struct cart* cart_control(struct cart* cart,int index){
         printf("1 remove\n");
         printf("2 edit quantity\n");
         printf("product: %s\n",row->product);
-        printf("price: %.2f\n",row->price);
+        printf("price: %.1f\n",row->price);
         printf("quantity: %d\n",quantity);
         bool check;
         do{
diff --git a/sorting.h b/sorting.h
index 638b127..4467cc7 100644
--- a/sorting.h
+++ b/sorting.h
@@ -4,9 +4,21 @@ typedef struct Map{
 }Map;
 
 int compare_decending(const void *a, const void *b){
+    if((*(struct Map *)b).value == NULL){//for dont sort new item
+        return -1;
+    }else if((*(struct Map *)a).value == NULL){
+        return 1;
+
+    }
     return (*(struct Map *)b).value - (*(struct Map *)a).value;
 }
 int compare_ascending(const void *a, const void *b){
+    if((*(struct Map *)b).value == NULL){
+        return -1;
+    }else if((*(struct Map *)a).value == NULL){
+        return 1;
+
+    }
     return (*(struct Map *)a).value - (*(struct Map *)b).value;
 }