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Fetch an element of a list by index

Given the list [One, Two, Three, Four, Five], fetch the third element ('Three')
python
list = ['One', 'Two', 'Three', 'Four', 'Five']
list[2]
cpp
String^ result = list[2];
clojure
(nth '[One Two Three Four Five] 2)

Fetch the last element of a list

Given the list [Red, Green, Blue], access the last element ('Blue')
python
list = ['Red', 'Green', 'Blue']
list[-1]
cpp
String^ result = list[list->Count - 1];
string last_elem = lst.back();
clojure
(last '[One Two Three Four Five])

Find the common items in two lists

Given two lists, find the common items. E.g. given beans = ['broad', 'mung', 'black', 'red', 'white'] and colors = ['black', 'red', 'blue', 'green'], what are the bean varieties that are also color names?
python
beans = ['broad', 'mung', 'black', 'red', 'white']
colors = ['black', 'red', 'blue', 'green']

common = [b for b in beans if b in colors]
beans = ['broad', 'mung', 'black', 'red', 'white']
colors = ['black', 'red', 'blue', 'green']

common = set(beans) & set(colors)
cpp
array<String^>^ inbeans = {"broad", "mung", "black", "red", "white"};
Generic::ICollection<String^>^ beans = makeSET<String^>(gcnew Generic::List<String^>((Generic::IEnumerable<String^>^) inbeans));

array<String^>^ incolors = {"black", "red", "blue", "green"};
Generic::ICollection<String^>^ colors = makeSET<String^>(gcnew Generic::List<String^>((Generic::IEnumerable<String^>^) incolors));

Generic::ICollection<String^>^ result = intersectSET<String^>(beans, colors);
clojure
(use 'clojure.set)

(let [beans '[broad mung black red white]
colors '[black red blue green]]
(intersection (set beans) (set colors)))

Display the unique items in a list

Display the unique items in a list, e.g. given ages = [18, 16, 17, 18, 16, 19, 14, 17, 19, 18], display the unique elements, i.e. with duplicates removed.
python
ages = [18, 16, 17, 18, 16, 19, 14, 17, 19, 18]

unique_ages = list(set(ages))
cpp
array<int>^ input = {18, 16, 17, 18, 16, 19, 14, 17, 19, 18};
Generic::List<int>^ ages = gcnew Generic::List<int>((Generic::IEnumerable<int>^) input);

Generic::ICollection<int>^ result = makeSET<int>(ages);
list<int> input;
input += 18, 16, 17, 18, 16, 19, 14, 17, 19, 18;
input.sort();
unique_copy(input.begin(), input.end(), ostream_iterator<int>(cout, "\n"));
clojure
;; returns a set
(set [18, 16, 17, 18, 16, 19, 14, 17, 19, 18])
;;#{14 16 17 18 19}

;; returns a lazy sequence of the unique elements
(distinct [18, 16, 17, 18, 16, 19, 14, 17, 19, 18])
;;(18 16 17 19 14)