SHELL

Set

Set<String> names = new HashSet<>();
names.add("John");
names.add("Jack");
names.add("John");
System.out.println(names); // [John, Jack]

names.remove("John");

boolean contains = names.contains("Jack"); // true

for (String name: names) {
    System.out.println(name);
}

SET

num |= 1 << x; //SET 

set

set [--abefhkmnptuvxBCEHPT] [-o option-name] [argument …]
set [+abefhkmnptuvxBCEHPT] [+o option-name] [argument …]

set

request.session['key'] = 'value'

set

// Needed Output
Set(3) {10, 20, 2}
2