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Define an initial map

Define the map {circle:1, triangle:3, square:4}

Check if a key exists in a map

Given a map pets {joe:cat,mary:turtle,bill:canary} print "ok" if an pet exists for "mary"

Retrieve a value from a map

Given a map pets {joe:cat,mary:turtle,bill:canary} print the pet for "joe" ("cat")

Add an entry to a map

Given an empty pets map, add the mapping from "rob" to "dog"

Remove an entry from a map

Given a map pets {joe:cat,mary:turtle,bill:canary} remove the mapping for "bill" and print "canary"

Create a histogram map from a list

Given the list [a,b,a,c,b,b], produce a map {a:2, b:3, c:1} which contains the count of each unique item in the list

Categorise a list

Given the list [one, two, three, four, five] produce a map {3:[one, two], 4:[four, five], 5:[three]} which sorts elements into map entries based on their length