first commit of lab4

src/Main.java

+import com.itextpdf.text.pdf.PdfReader;
+
+public class Main {
+    public static void main(String[] args) {
+
+        try {
+            PdfReader pdfReader = new PdfReader("test.pdf");
+            System.out.println(pdfReader.getNumberOfPages());
+        }catch (Exception e){
+            System.out.println(e);
+        }
+    }
+}