feat: add Lab4

Lab1/Customer.java

@@ -0,0 +1,34 @@
+/**
+ * This is a data class which holds information about the Customer.
+ * It has a incrementing counter for the customer id;
+ * 
+ * @author Yadunand Prem
+ * @version CS2030S AY22/23 Semester 2
+ */
+public class Customer {
+  private static int lastId = 0;
+
+  private final int id;
+  private final double serviceTime;
+  private final double arrivalTIme;
+
+  public Customer(double serviceTime, double arrivalTime) {
+    this.id = lastId++;
+    this.serviceTime = serviceTime;
+    this.arrivalTIme = arrivalTime;
+  }
+
+  public double getServiceTime() {
+    return this.serviceTime;
+  }
+
+  public double getArrivalTIme() {
+    return arrivalTIme;
+  }
+
+  @Override
+  public String toString() {
+    return "C" + id;
+  }
+
+}