Data Structures Cup 2025 (The Final Competition)

Complete the missing line from the circular array EnQueue() algorithm?

1.If (isFull()) Then Display ("Queue is overflow”);

Return[End If]

2.Set Queue[ rear_index ] = value

3....................................................................................

4.Set Count = Count + 1

5.End

• Set rear_index = rear_index + 1

• Set rear_index = (rear_index + 1 ) mod size

• Set front_index = (front_index + 1 ) mod size

• Set rear_index = front_index % size

Which line completes the priority queue for removeMax() algorithm?

1.If (isEmpty()) return null;

2.Set temp = front_index

3..................................................................

4.Return temp;

• front_index = front_index.next

• rear_index = rear_index.prev

• front_index = null

• rear_index = front_index

Which algorithm is responsible for DeQueue in a circular linked list?

• 1.If (isEmpty ()) Then Display ("Queue is underflow ”);

  Return; [End If]

  2.Set front = front.Next

  4.Set Count = Count -1

  5.End

• 1.If (isEmpty ()) Then Display ("Queue is underflow ”);

  Return; [End If]

  2.Set rear= rear.Next

  3.Set rear. Next = front

  4.Set Count = Count -1

  5.End

• 1.If (isEmpty ()) Then Display ("Queue is underflow ”);

  Return; [End If]

  2.Set front = front.Next

  3.Set rear. Next = front

  4.Set Count = Count -1

  5.End

• 1.If (isEmpty ()) Then Display ("Queue is underflow ”);

  Return; [End If]

  2.Set front.Next=front

  3.Set rear. Next = front

  4.Set Count = Count -1

  5.End

Complete the following EnQueue algorithm using a linear linked-list to locate the correct position for inserting the new node in a priority queue?

1.Set Node newNode = new Node( value, key , null), Current = front, Prev =null

/* Missing Lines */

3. If (Prev=null) Then front = newNode, Else Prev.next=newNode [End If]

4. Set newNode.next = current

5. Set size=size+1

5.End

• 2.Repeat while (Current ! = null and key > Current.key )

  1.Set Prev = Current;

  2.Set Current = Current.next;

  [ End Loop ]

• 2.Repeat while (Current = null and key < Current.key )

  1.Set Prev = Current;

  2.Set Current = Current.next;

  [ End Loop ]

• 2.Repeat while (Current ! = null and key < Current.key )

  1.Set Current=Prev;

  2.Set Current = Current.next;

  [ End Loop ]

• 2.Repeat while (Current ! = null and key < Current.key )

  1.Set Prev = Current;

  2.Set Current = Current.next;

  [ End Loop ]

What is the most suitable data structure when patients arrive at an emergency room, they are assessed and assigned based on the severity of their condition. Critical patients (such as those with life-threatening injuries) are treated before those with less urgent issues (like a mild cold), regardless of arrival time. This ensures that medical resources are allocated efficiently and lives are saved?

• Tree

• Circular Linked-List

• Priority Queue

• Stack

What is the most suitable data structure for designing database indices, that enables fast searching, insertion, and deletion of records, which is critical for large databases where performance matters?

• Stack

• Binary Search Tree

• Priority Queue

• Graph

This algorithm is responsible for which type of binary tree traversal?

algorithm: fun

Input: BinaryTreeNodes

1.if (bt== null) return;

2.fun(bt.leftChild)

3.Display(bt.value)

4.fun(bt.rightChild)

5.End

• Level-order

• PostOrder

• PreOrder

• InOrder

4. When inserting "7" into a BST with root=5 (left=3, right=8), where will it be placed?

• Left child of 8

• Right child of 8

• Left child of 5

• Right child of 3

Given the tree in the image, what is the PostOrder traversal?

• A, D, E, B, F, C

• E, B, D, F, C, A

• D, E, B, F, C, A

• E, B, F, C, A, D

What is the function of XYZ method?

 BinaryTreeNode XYZ(BinaryTreeNode node) {

        if (isEmpty()) {

            return null;}

        while (node.leftChild != null) {

            node = node.leftChild;}

           return node;}

• Searching for any value

• Searching for the minimum value

• Searching for maximum value

• Searching for XYZ value