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CODING EXERCISES

Small problems. Strong instincts.

Choose a language and build confidence with focused exercises, helpful tests, and explanations that teach the underlying pattern.

HTMLbeginner

Repair a heading outline

Turn visually emphasized text into a logical heading hierarchy for a city cycling guide. The outline should make sense even when read without the paragraphs.

HTMLbeginner

Structure a semantic news article

Replace generic containers with meaningful landmarks and article elements so a short community news page has a clear, navigable structure.

JavaScriptbeginner

Group orders by status

Return an object whose keys are order statuses and whose values preserve the matching orders in their original order.

JavaScriptbeginner

Mask an email address for display

Return a privacy-friendly display value for a valid email: retain the first local-part character, replace the remaining local characters with asterisks, and keep the domain unchanged. Return null for malformed input.

Your privacy choices

Small problems. Strong instincts.

Repair a heading outline

Structure a semantic news article

Group orders by status

Mask an email address for display

Normalize a list of tags

Reverse the words

Count unique words

Find duplicates

Normalize an email address

Build a filtered workshop availability report

Label customers who have no phone

Look up one customer by email