Scope CS Thinking Example 1
Follow the full solution, then compare it with the other examples linked below.
Example 1
mediumWhat is the output? SET x = 10. FUNCTION addFive(): SET x = 5. RETURN x + 5. OUTPUT addFive(). OUTPUT x.
Solution
- 1 Step 1: The function creates a local variable x = 5 (separate from the global x = 10).
- 2 Step 2: addFive() returns 5 + 5 = 10. First output: 10.
- 3 Step 3: The global x is still 10 (unchanged by the function). Second output: 10.
Answer
10, then 10. The function's local x does not affect the global x.
Scope determines where a variable can be accessed. Local variables inside a function are separate from global variables with the same name. This prevents functions from accidentally modifying external state.
About Scope
The region of a program where a variable is accessible. Variables defined inside a function have local scope and exist only within that function. Variables defined outside all functions have global scope and are accessible from anywhere in the program.
Learn more about Scope →More Scope Examples
Example 2 hard
Explain why using global variables inside functions is generally discouraged.
Example 3 mediumWhat is the output? SET y = 100. FUNCTION test(): OUTPUT y. test(). Will this work, or will there be
Example 4 mediumWhat is the output? Explain any errors. SET count = 0 FUNCTION increment() SET count = count + 1