added solution of task

src/main/java/core/basesyntax/WorkWithFile.java

@@ -1,7 +1,46 @@
 package core.basesyntax;
 
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+
 public class WorkWithFile {
     public void getStatistic(String fromFileName, String toFileName) {
+        // Variables to store the total supply and buy amounts
+        int supply = 0;
+        int buy = 0;
+        int result;
+        final String supplyStr = "supply";
+        final String buyStr = "buy";
+        // Step 1: Read the CSV file
+        try (BufferedReader bufferedReader = new BufferedReader(new FileReader(fromFileName))) {
+            String line;
+            while ((line = bufferedReader.readLine()) != null) {
+                String[] lineSplit = line.split(",");
+                int value = Integer.parseInt(lineSplit[1].trim());
+                String lineEach = lineSplit[0].trim();
+                if (lineEach.equals(supplyStr)) {
+                    supply += value;
+                } else if (lineEach.equals(buyStr)) {
+                    buy += value;
+                }
+            }
+            result = supply - buy;
+        } catch (IOException e) {
+            throw new RuntimeException("Error in reading CSV file", e);
+        }
+
+        StringBuilder builderReport = new StringBuilder();
+        builderReport.append("supply,").append(supply).append(System.lineSeparator());
+        builderReport.append("buy,").append(buy).append(System.lineSeparator());
+        builderReport.append("result,").append(result).append(System.lineSeparator());
 
+        try (BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(toFileName))) {
+            bufferedWriter.write(builderReport.toString());
+        } catch (IOException e) {
+            throw new RuntimeException("Error in writing file", e);
+        }
     }
 }