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Frequency Counting

6 min · OCaml examples

Use a dictionary to count how many times each value appears.

OCaml · Frequency Counting0/5 cleared

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Many problems boil down to "how often does each thing show up?" OCaml's Hashtbl module is perfect: keys are the items, values are counts.

Increment with Hashtbl.replace counts x (count + 1), using Hashtbl.find_opt to read the current count (or 0) as you scan the input once.

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