Notes

• Set is not sequence, cannot be got by index and slicing
• python
  • frozenset is immutable set
• go
  • No primitive set and related lib

Operations

### python ###

# create
demoset = set()
demoset = set(list) # input args is sequence
demoset.add(element)

# retrieve
demoset.pop()

# update
demoset.update(other_set) # merge

# delete
demoset.remove(element)
demoset.discard(element)

# others
&, |, -, ^
==, !=, >, >=, <, <=