v0.40: Create exercises. Challenge the community.

zigzag_letters

Your mission

Implement zigzag_letters, a text formatter that alternates letter casing.

See it in action

zigzag_letters("grade")

Expected result

"gRaDe"

Your checklist

For your own tracking. Tests grade your code.

Create zigzag_case.py.
Expose def zigzag_letters(text: str) -> str:.
Return a new string where alphabetic characters alternate between lowercase and uppercase.
The first alphabetic character must be lowercase, the second uppercase, the third lowercase, and so on.
Non-alphabetic characters must stay unchanged.
Non-alphabetic characters do not advance the alternating letter counter.
The alternation does not reset after spaces or punctuation.

More examples

zigzag_letters("ab-cd ef")

Expected result

"aB-cD eF"

Constraints

Expected files

zigzag_case.py

Allowed functions

None. Write every helper yourself.

zigzag_letters

Your mission

Implement zigzag_letters, a text formatter that alternates letter casing.

See it in action

zigzag_letters("grade")

Expected result

"gRaDe"

Your checklist

For your own tracking. Tests grade your code.

Create zigzag_case.py.
Expose def zigzag_letters(text: str) -> str:.
Return a new string where alphabetic characters alternate between lowercase and uppercase.
The first alphabetic character must be lowercase, the second uppercase, the third lowercase, and so on.
Non-alphabetic characters must stay unchanged.
Non-alphabetic characters do not advance the alternating letter counter.
The alternation does not reset after spaces or punctuation.

More examples

zigzag_letters("ab-cd ef")

Expected result

"aB-cD eF"

Constraints

Expected files

zigzag_case.py

Allowed functions

None. Write every helper yourself.

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01Plain wordWaiting

02Spaces do not reset the alternating sequenceWaiting

03Digits do not advance the letter counterWaiting

04Punctuation is preservedWaiting

05Empty stringWaiting

06Alternation continues after spacesWaiting

07Symbols between lettersWaiting

zigzag_letters

Your mission

Implement zigzag_letters, a text formatter that alternates letter casing.

See it in action

zigzag_letters("grade")

Expected result

"gRaDe"

Your checklist

For your own tracking. Tests grade your code.

Create zigzag_case.py.
Expose def zigzag_letters(text: str) -> str:.
Return a new string where alphabetic characters alternate between lowercase and uppercase.
The first alphabetic character must be lowercase, the second uppercase, the third lowercase, and so on.
Non-alphabetic characters must stay unchanged.
Non-alphabetic characters do not advance the alternating letter counter.
The alternation does not reset after spaces or punctuation.

More examples

zigzag_letters("ab-cd ef")

Expected result

"aB-cD eF"

Constraints

Expected files

zigzag_case.py

Allowed functions

None. Write every helper yourself.

v0.40: Create exercises. Challenge the community.

Meet Studio →

zigzag_letters

Your mission

Implement zigzag_letters, a text formatter that alternates letter casing.

See it in action

zigzag_letters("grade")

Expected result

"gRaDe"

Your checklist

For your own tracking. Tests grade your code.

Create zigzag_case.py.
Expose def zigzag_letters(text: str) -> str:.
Return a new string where alphabetic characters alternate between lowercase and uppercase.
The first alphabetic character must be lowercase, the second uppercase, the third lowercase, and so on.
Non-alphabetic characters must stay unchanged.
Non-alphabetic characters do not advance the alternating letter counter.
The alternation does not reset after spaces or punctuation.

More examples

zigzag_letters("ab-cd ef")

Expected result

"aB-cD eF"

Constraints

Expected files

zigzag_case.py

Allowed functions

None. Write every helper yourself.

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01Plain wordWaiting

02Spaces do not reset the alternating sequenceWaiting

03Digits do not advance the letter counterWaiting

04Punctuation is preservedWaiting

05Empty stringWaiting

06Alternation continues after spacesWaiting

07Symbols between lettersWaiting