Update BasicQueue.java

Author: Gourav-s12

Data Structure/Queue/Basic Queue/BasicQueue.java

@@ -1,3 +1,11 @@
+/*Queue is an abstract data structure, somewhat similar to Stacks. 
+Unlike stacks, a queue is open at both its ends. One end is always
+used to insert data (enqueue) and the other is used to remove data
+(dequeue). Queue follows First-In-First-Out methodology, i.e., the
+data item stored first will be accessed first.*/
+
+// this is the implementation of a basic queue 
+
 import java.util.Arrays;
 import java.util.Scanner;
 class QueUe{
@@ -8,42 +16,43 @@ class QueUe{
 
     QueUe(int capacity){
         size=capacity;
-        Qarray = new int[capacity];
-        rear=-1;
-        front=-1;
-    }
+        Qarray = new int[capacity];//creating a queue as a array
+        rear=-1;// initializing rear
+        front=-1;//initializing front
+	   //queue is empty at first 
+     }
 
     void display(){
-        System.out.println(Arrays.toString(Qarray));
+        System.out.println(Arrays.toString(Qarray)); //print the queue
     }
 
     void value(){
-        System.out.println("front:"+front+"\t rare:"+rear);
+        System.out.println("front:"+front+"\t rare:"+rear); //to see the current rear & front
     }
 
     void peek()
 	{
 		if (isEmpty()) 
 		{
-			System.out.println("Queue empty!");
+			System.out.println("Queue empty!");//if queue empty-> no element to peek
 			return;
 		}
-		 System.out.println("peek value is "+Qarray[front]);
+		 System.out.println("peek value is "+Qarray[front]);//peeking the front value
 	}
 
     void enqueue(int val){
         if (isFull())
 		{
 			System.out.println("queue is full!");
-			return;
+			return; //can not enter element if queue is full
 		}
         if(rear==-1){
-            front++;
+            front++; //for 1st element put in queue from queue were empty 
         }
 		System.out.println("Adding " + val);
 
-		rear++ ;
-		Qarray[rear] = val;
+		rear++ ; //adding new element in rear -> rear++
+		Qarray[rear] = val; //putting the value
     }
 
     void dequeue()
@@ -52,26 +61,26 @@ void dequeue()
 		if (isEmpty())
 		{
 			System.out.println("queue is empty");
-			return;
+			return; // if queue is empty -> no element to delete 
 		}
 
 		System.out.println("Deleting " + Qarray[front]);
         if(front==rear){
             front=-1;
-            rear=-1;//last element
-            return;
+            rear=-1;//when only 1 element was in queue , now deleted
+            return; //now queue is empty 
         }
-		front++;
+		front++; //deleting element-> front ++
 	}
 
 	Boolean isFull()
 	{
-		return (rear==size-1);
+		return (rear==size-1); // check if queue is full
 	}
 
 	Boolean isEmpty()
 	{
-		return (front==-1);
+		return (front==-1); // check if queue is empty 
 	}
 }
 class BasicQueue { 
@@ -80,8 +89,9 @@ public static void main(String[] args)
     { 
         QueUe que = new QueUe(4);
 
+	   //just some random queue function sequence 
 		que.enqueue(5);
-	    que.peek();
+	        que.peek();
 		que.dequeue();
 		que.peek();
 		que.enqueue(20);