diff --git a/TravelCostCalculator.java b/TravelCostCalculator.java
index 6f89acb..0a6f154 100644
--- a/TravelCostCalculator.java
+++ b/TravelCostCalculator.java
@@ -1,3 +1,4 @@
+//EG_2020_3990
 import java.io.BufferedReader;
 import java.io.FileReader;
 import java.io.IOException;
@@ -6,70 +7,76 @@
 import java.util.Map;
 
 public class TravelCostCalculator {
-    static Map<String, Double> a = new HashMap<>();
-    static Map<String, Double> b = new HashMap<>();
-    static Map<String, Double> c = new HashMap<>();
+    private static final Map<String, Double> hotel = new HashMap<>();
+    private static final Map<String, Double> exchange = new HashMap<>();
+    private static final Map<String, Double> flight = new HashMap<>();
 
-    static void l1(String file) throws IOException {
-        BufferedReader reader = new BufferedReader(new FileReader(file));
-        String i; 
-        while ((i = reader.readLine()) != null) {
-            String[] p = i.split(",");
-            a.put(p[0].toUpperCase(), Double.parseDouble(p[1]));
+    // load hotel from line
+    private static void loadHotel(String file) throws IOException {
+        try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                String[] part = line.split(",");
+                hotelRates.put(part[0].toUpperCase(), Double.parseDouble(part[1]));
+            }
         }
     }
 
-    static void l2(String file) throws IOException {
+    // load exchange from line
+    static void loadExchange(String file) throws IOException {
         BufferedReader reader = new BufferedReader(new FileReader(file));
-        String i;
-        while ((i = reader.readLine()) != null) {
-            String[] p = i.split(",");
-            b.put(p[0].toUpperCase(), Double.parseDouble(p[1]));
+        String line;
+        while ((line = reader.readLine()) != null) {
+            String[] part = line.split(",");
+            b.put(part[0].toUpperCase(), Double.parseDouble(part[1]));
         }
     }
 
-    static void l3(String file) throws IOException {
-        BufferedReader reader = new BufferedReader(new FileReader(file));
-        String i;
-        while ((i = reader.readLine()) != null) {
-            String[] p = i.split(",");
-            c.put(p[0].toUpperCase(), Double.parseDouble(p[1]));
+    // load flight from line
+    private static void loadFlight(String file) throws IOException {
+        try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                String[] part = line.split(",");
+                flightCosts.put(part[0].toUpperCase(), Double.parseDouble(part[1]));
+            }
         }
     }
 
     public static void main(String[] args) {
         try {
-            l1("data/hotel_rates.csv");
-            l2("data/exchange_rates.csv");
-            l3("data/flight_costs.csv");
+            loadHotel("data/hotel_rates.csv");
+            loadExchange("data/exchange_rates.csv");
+            loadFlight("data/flight_costs.csv");
 
             BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
 
             System.out.print("Enter your destination: ");
             String destination = reader.readLine().toUpperCase();
 
-            double flight_cost = c.getOrDefault(destination, 0.0);
-            double hotel_cost = a.getOrDefault(destination, 0.0);
+            double flightCost = flight.getOrDefault(destination, 0.0);
+            double hotelCost = hotel.getOrDefault(destination, 0.0);
 
             System.out.print("Enter your stay duration in days: ");
-            int stay_duration = Integer.parseInt(reader.readLine());
-            hotel_cost *= stay_duration;
+            int stayDuration = Integer.parseInt(reader.readLine());
+            hotelCost *= stayDuration;
 
-            double total_cost_usd = flight_cost + hotel_cost;
+            double totalCostUSD = flightCost + hotelCost;
 
-            System.out.printf("Flight cost: USD %.2f\n", flight_cost);
-            System.out.printf("Hotel cost (%d days): USD %.2f\n", stay_duration, hotel_cost);
-            System.out.printf("Total: USD %.2f\n", total_cost_usd);
+            System.out.printf("Flight cost: USD %.2f\n", flightCost);
+            System.out.printf("Hotel cost (%d days): USD %.2f\n", stayDuration, hotelCost);
+            System.out.printf("Total: USD %.2f\n", totalCostUSD);
 
-            String[] available_currencies = b.keySet().toArray(new String[0]);
-            System.out.print("Select your currency for final price estimation(" + String.join(", ", available_currencies) + "): ");
-            String selected_currency = reader.readLine();
+            String[] availableCurrencies = exchange.keySet().toArray(new String[0]);
+            System.out.print("Select your currency for final price estimation(" + String.join(", ", availableCurrencies) + "): ");
+            String selectedCurrency = reader.readLine();
 
-            double final_price_local_currency = total_cost_usd * b.get(selected_currency);
+            double finalPriceLocalCurrency = totalCostUSD * exchange.get(selectedCurrency);
 
-            System.out.printf("Total in %s: %.2f\n", selected_currency, final_price_local_currency);
+            System.out.printf("Total in %s: %.2f\n", selectedCurrency, finalPriceLocalCurrency);
+            
         } catch (IOException e) {
             e.printStackTrace();
         }
     }
-}
+}
\ No newline at end of file