reading from a barcode scanner and displaying the total of scanned products

hello guys am trying to read barcodes using a CCD camera module, and diplay the product details, the code is working so far but I am not able to get the total amount to display since the database uses an array of strings and not integers.

[#include <LiquidCrystal.h>   
#include <PS2Keyboard.h>

const int DataPin = 2;
const int IRQpin =  3;


LiquidCrystal lcd(12, 11, 7, 6, 5, 4);
PS2Keyboard barCodeScanner;

 //creating database
const int NUMBER_OF_PRODUCTS = 10;
const int MAX_SCANNED_PRODUCTS = 15;

String ERROR_MSG = "Invalid barcode";
String productNames[NUMBER_OF_PRODUCTS] = {"Product_1","Product_2","Product_3","Product_4","Product_5","Product_6","Product_7","Product_8","Product_9","Product_10"};
String productBarCodes[NUMBER_OF_PRODUCTS] ={"61600997","5011501040520","6003001005610","6161101530743","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf"};
String productPrices[NUMBER_OF_PRODUCTS] ={"120","200","250","900","60","300","200","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf","ssdfsdgsdfgsdf"};
String scannedProducts[MAX_SCANNED_PRODUCTS] = {"xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx","xxx"};

String addProductPrices="";
int numScannedProducts = 0;
String newProductPrices="" ;
String newProductBarCode = "";
String newProductName = "";
bool shoppingListSent = false;

int productIndex(String scannedBarcode) {
  for (int i=0; i<NUMBER_OF_PRODUCTS; i++) {
     if (scannedBarcode == productBarCodes[i]) {
       
       return i;
     }
  }
  
  return -1;
}

void addNewProduct(String newProductName){
  scannedProducts[numScannedProducts++] = newProductName;//adds the number of products
 
  
}

void setup() {
  Serial.begin(9600);
  barCodeScanner.begin(DataPin, IRQpin);
}
  void loop() {

     if (barCodeScanner.available() /*&& (buttonState != HIGH)*/ && (!shoppingListSent) && (numScannedProducts < MAX_SCANNED_PRODUCTS)){
    
    // read the next key
    char c = barCodeScanner.read();
    
    // check for some of the special keys
    if (c == PS2_ENTER) {
      newProductName = productNames[productIndex(newProductBarCode)]; //displays the product names
      newProductPrices = productPrices[productIndex(newProductBarCode)]; //displays the product price
    
      lcd.clear();
      addNewProduct(newProductName);
     // addNewProduct(int newProductPrices);
      //lcd.print("Pr.#" + String(numScannedProducts) + ": " + newProductName);
      Serial.println("NoP=" + String(numScannedProducts) + ": " +  newProductName );
      Serial.println("sh= "  + newProductPrices );
      Serial.println("Total= " );
      newProductBarCode = "";
    } else {
      newProductBarCode.concat(c);
      Serial.print(c);
    }
  
    }
  }]

edited.ino (2.45 KB)

Oh, if only us poor souls on mobile devices could see your code.
Ho-hum.