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Implement a Queue Using an Array.

Certification: Basic Level Accuracy: 66.67% Submissions: 3 Points: 5

Write a C# program to implement a queue data structure using an array. A queue is a linear data structure that follows the First In First Out (FIFO) principle.

Example 1
    
  
  • Input: 
      
      
    • Enqueue(10)
      • 
      
    • Enqueue(20)
      • 
      
    • Enqueue(30)
      • 
      
    • Dequeue()
      • 
      
    • Peek()
      • 
      
    • IsEmpty()
      • 
    
    
  
    • 
  
  • Output: 
      
      
    • 10
      • 
      
    • 20
      • 
      
    • False
      • 
    
    
  
    • 
  
  • Explanation: 
      
      
    • Step 1: Enqueue 10, 20, and 30 to get queue [10, 20, 30].
      • 
      
    • Step 2: Dequeue() removes and returns the front element 10.
      • 
      
    • Step 3: Peek() returns the current front element 20 without removing it.
      • 
      
    • Step 4: IsEmpty() returns false as the queue still has elements.
      • 
    
    
  
    •
Example 2
    
  
  • Input: 
      
      
    • Enqueue(5)
      • 
      
    • Dequeue()
      • 
      
    • Dequeue()
      • 
      
    • IsEmpty()
      • 
    
    
  
    • 
  
  • Output: 
      
      
    • 5
      • 
      
    • Queue Underflow
      • 
      
    • True
      • 
    
    
  
    • 
  
  • Explanation: 
      
      
    • Step 1: Enqueue 5 to get queue [5].
      • 
      
    • Step 2: First Dequeue() removes and returns 5.
      • 
      
    • Step 3: Second Dequeue() tries to remove from an empty queue, resulting in "Queue Underflow".
      • 
      
    • Step 4: IsEmpty() returns true as the queue is now empty.
      • 
    
    
  
    •
Constraints
    
  
  • The capacity of the queue is fixed and determined at initialization
    • 
  
  • 0 ≤ Number of operations ≤ 1000
    • 
  
  • 0 ≤ Values enqueued to the queue ≤ 10^4
    • 
  
  • Time Complexity for all operations: O(1)
    • 
  
  • Space Complexity: O(n) where n is the queue capacity
    •
ArraysQueueDeloittePhillips
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Hint
Solution

Solution Hints

    
  
  • Use an array to store elements and variables to track the front and rear indices.
    • 
  
  • Implement boundary checks to avoid queue overflow and underflow.
    • 
  
  • Initialize the front and rear indices to -1 to indicate an empty queue.
    • 
  
  • Handle the case when the queue becomes empty after a dequeue operation.
    • 
  
  • Consider implementing a circular queue to utilize the array space efficiently.
    •

Steps to solve by this approach:

 Step 1: Create a class with an array, front and rear index variables, and a capacity variable.
 Step 2: Initialize both front and rear indices to -1 to represent an empty queue.
 Step 3: Implement Enqueue by incrementing the rear index and adding the value if the queue is not full.
 Step 4: Implement Dequeue by returning the front value and incrementing the front index if the queue is not empty.
 Step 5: Implement special case handling for when the queue becomes empty after a dequeue operation.

Submitted Code :