Inside a Hash Map Lookup
The lesson opens with map.get("pear") and animates the hidden work: compute a hash, select a candidate bucket, inspect the slot or chain, compare the stored key, and return the value. It then contrasts chaining with open addressing and shows why a collision still requires an equality check.
The closing scene connects load factor and resize work to expected lookup cost, then follows the same request through contiguous and pointer-heavy layouts. The narration avoids promising one probe per lookup because collision policy and table state matter. Companion material: hash map article, lookup trace, and interactive flow.
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