“Collections.defaultdict (set)” Kode Jawaban

Dari Koleksi Impor DefaultDict

>>> s = [('yellow', 1), ('blue', 2), ('yellow', 3), ('blue', 4), ('red', 1)]
>>> d = defaultdict(list)
>>> for k, v in s:
...     d[k].append(v)
...
>>> d.items()
[('blue', [2, 4]), ('red', [1]), ('yellow', [1, 3])]

Unusual Unicorn

Collections.defaultdict (set)

defaultdict means that if a key is not found in the dictionary,
then instead of a KeyError being thrown, a new entry is created. 
The type of this new entry is given by the argument of defaultdict.

For example:

somedict = {}
print(somedict[3]) # KeyError

someddict = defaultdict(int)
print(someddict[3]) # print int(), thus 0

>>> from collections import defaultdict

Concerned Crab

Jelajahi jawaban kode populer menurut bahasa

Jelajahi bahasa kode lainnya

Shell/Bash

C++

CSS

HTML

Java

JavaScript

Objective-C

PHP

Python

Sql

Swift

Ruby

TypeScript

Kotlin

Assembly

VBA

Scala

Rust

Dart

Elixir

Clojure

Haskell

Matlab

Erlang

Cobol

Fortran

Scheme

Perl

Groovy

Lua

Julia

Delphi

Abap

Lisp

Prolog

Pascal

ActionScript

Basic

Solidity

PowerShell

GDScript

Excel