feat: add Deque data structure with tests and README#2157
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trekhleb merged 3 commits intoJun 19, 2026
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lisagorewitdecker
approved these changes
May 29, 2026
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What this PR adds
A Deque (double-ended queue) data structure backed by the existing LinkedList.
Why it belongs here
The repo has Queue and Stack but no Deque. A Deque generalises both —
elements can be added/removed from either end in O(1) time.
Files added
src/data-structures/deque/Deque.js— implementationsrc/data-structures/deque/__test__/Deque.test.js— 14 tests, 100% coveragesrc/data-structures/deque/README.md— explanation, complexity table, use cases, referencesChecklist