Practice Scope in CS Thinking
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
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.
Scope is like rooms in a house. A variable created inside a room (function) can only be seen from inside that room. A variable in the hallway (global) can be seen from everywhere.
Example 1
mediumWhat is the output? SET x = 10. FUNCTION addFive(): SET x = 5. RETURN x + 5. OUTPUT addFive(). OUTPUT x.
Example 2
hardExplain 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 an error?
Example 4
mediumWhat is the output? Explain any errors.
SET count = 0
FUNCTION increment()
SET count = count + 1
SET bonus = 10
END FUNCTION
increment()
OUTPUT count
OUTPUT bonus