评分标准模式

Generic MS Template

Mark Scheme — Recursive Function (6 marks)

• M1 Correct base case condition
• A1 Correct base case return value
• A1 Correct recursive call with reduced argument
• A1 Correct operation on recursive result
• A1 Correct return in recursive branch
• A1 Correct function signature (name, parameters, return type)

Mark Scheme — Convert Iterative to Recursive (5 marks)

• M1 Identifies correct parameter(s) for recursion
• A1 Base case matching loop termination
• A1 Recursive call updates the loop variable
• A1 Result accumulated correctly
• A1 Returns the final accumulated value

Mark Scheme — Trace Recursion (3 marks)

• M1 Shows all recursive calls in correct order
• A1 Correct return values for each call
• A1 Correct final answer

Common MS Keywords

Keyword	Meaning
M1	Method mark — correct approach/concept
A1	Accuracy mark — correct implementation/value
B1	Independent mark — no dependency on M marks
cao	Correct answer only
oe	Or equivalent (any correct alternative)

Mark Allocation Patterns

Exam Question	Topic	Marks
Write recursive function f(x)	Factorial / Power	5
Write recursive procedure p(x)	Output / Print	5
Convert iterative → recursive	Array sum / Search	4–6
Trace recursive call	Any recursive function	2–3
State output of recursion	String / Integer output	2