OCR A-Level Computer Science Algorithms and programming (02), June 2025
Every question from OCR A-Level Computer Science Algorithms and programming (02), June 2025 (H446): 8 questions, 140 marks, each with its mark scheme and topic.
- Question 1 22 marks
Explain the operation of bubble sort and insertion sort, and analyze pseudocode implementing a recursive quick sort algorithm.
2.2 Problem solving and programming · 2.3 Algorithms · 2.2.1 Programming techniques · 2.2.2 Computational methods · 2.3.1 Algorithms
- Question 2 14 marks
Compare the use of linear search and binary search for 50 million sorted user records referencing Big-O complexity, and explain the concept and business uses of data mining.
2.1 Elements of computational thinking · 2.2 Problem solving and programming · 2.3 Algorithms · 2.1.2 Thinking ahead · 2.2.2 Computational methods · 2.3.1 Algorithms
- Question 3 17 marks
Demonstrate the operation of a stack, complete a push function, write a pop function, and write an algorithm using the stack to reverse 10 user-input characters.
1.4 Data types, data structures and algorithms · 2.2 Problem solving and programming · 2.3 Algorithms · 1.4.2 Data Structures · 2.2.1 Programming techniques · 2.3.1 Algorithms
- Question 4 9 marks
Discuss the features, execution of four instructions, and justification of pipelining for a processor executing millions of instructions.
1.1 The characteristics of contemporary processors, input, output and storage devices · 1.1.1 Structure and function of the processor
- Question 5 11 marks
Apply Dijkstra's algorithm to find the shortest path between planets in a directed graph, explain visualization, and describe how the A* algorithm uses heuristics.
1.4 Data types, data structures and algorithms · 2.2 Problem solving and programming · 2.3 Algorithms · 1.4.2 Data Structures · 2.2.2 Computational methods · 2.3.1 Algorithms
- Question 6 18 marks
Identify IDE debugging features, explain global vs local variables and parameter passing by value, and identify and correct errors in an array-processing pseudocode algorithm.
1.4 Data types, data structures and algorithms · 2.2 Problem solving and programming · 2.3 Algorithms · 1.4.2 Data Structures · 2.2.1 Programming techniques · 2.3.1 Algorithms
- Question 7 9 marks
Insert values into a binary search tree, describe the drawbacks of an unbalanced binary search tree, and state the post-order depth-first and breadth-first traversals of a tree.
1.4 Data types, data structures and algorithms · 2.3 Algorithms · 1.4.2 Data Structures · 2.3.1 Algorithms
- Question 8 40 marks
Describe linked list data structures, implement OOP methods for node and linkedList classes, design an algorithm to traverse, add, and remove nodes, identify computational methods, and evaluate OOP versus 2D array implementations in a 12-mark essay.
1.2 Software and software development · 1.4 Data types, data structures and algorithms · 2.1 Elements of computational thinking · 2.2 Problem solving and programming · 2.3 Algorithms · 1.2.4 Types of Programming Language · 1.4.2 Data Structures · 2.1.2 Thinking ahead · 2.2.1 Programming techniques · 2.2.2 Computational methods · 2.3.1 Algorithms