【3-1】
▲文字列の長さ
-------------------
>>> print(len('Hello World'))
11
-------------------


▲リストの要素数
-------------------
>>> list1 = ["apple", "orange", "lemon", "banana"]
>>> print(len(list1))
4
-------------------


▲辞書のオブジェクト数
-------------------
>>> dict1 = {1:"apple", 2:"orange", 3:"lemon", 4:"banana"}
>>> print(len(dict1))
4
-------------------


【3-2】
▲文字列
-------------------
>>> print(list('abc'))
['a', 'b', 'c']
>>> type(list('abc'))
<class 'list'>
-------------------


▲タプル
-------------------
>>> type((1, 2, 3))
<class 'tuple'>
>>> print(list((1, 2, 3)))
[1, 2, 3]
>>> type(list((1, 2, 3)))
<class 'list'>
-------------------


【3-3】
▲終了だけ設定
-------------------
>>> type(range(11))
<class 'range'>
>>> print(list(range(11)))
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
-------------------


▲開始，終了，ステップを設定
-------------------
>>> print(list(range(1, 11, 1)))
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
-------------------


▲ステップを変えてみる
-------------------
>>> print(list(range(1, 11, 3)))
[1, 4, 7, 10]
-------------------


▲マイナスのシーケンス
-------------------
>>> print(list(range(10, 0, -1)))
[10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
>>> print(list(range(10, 0, -2)))
[10, 8, 6, 4, 2]
-------------------


▲終了を0とした場合
-------------------
>>> print(list(range(0)))
[]
-------------------


▲小数のシーケンス
-------------------
>>> list1 = []
>>> for x in range(1,6):
	list1.append(x / 10)

>>>print(list1)
[0.1, 0.2, 0.3, 0.4, 0.5]
-------------------


▲九九表を作る
>>> num = range(1,10)
for x in num:
	list1 = []
	for y in num:
		list1.append(x * y)
	print(list1)
[1,2,3,4,5,6,7,8,9]
[2,4,6,8,10,12,14,16,18]
[3,6,9,12,15,18,21,24,27]
[4,8,12,16,20,24,28,32,36]
[5,10,15,20,25,30,35,40,45]
[6,12,18,24,30,36,42,48,54]
[7,14,21,28,35,42,49,56,63]
[8,16,24,32,40,48,56,64,72]
[9,18,27,36,45,54,63,72,81]


【3-4】
▲sort関数のデフォルト動作で並べ替え
-------------------
>>> list1 = ['apple', 'banana', 'lemon', 'orange']
>>> list1.sort()
>>> print(list1)
['apple', 'banana', 'lemon', 'orange']
-------------------


▲文字数で並べ替え
-------------------
>>> list1 = ['0', '0123', '01', '012']
>>> list1.sort(key=len)
>>> print(list1)
['0', '01', '012', '0123']
-------------------


▲整数で並べ替え
-------------------
>>> list1 = ['1000', '10', '1', '100']
>>> list1.sort(key=int)
>>> print(list1)
['1', '10', '100', '1000']
-------------------


▲小数で並べ替え
-------------------
>>> list1 = ['0.1', '12.3', '0.0']
>>> list1.sort(key=float)
>>> print(list1)
['0.0', '0.1', '12.3']
-------------------


▲大文字・小文字を考慮した並べ替え
-------------------
>>> list1 = ['Ronit', 'Dan', 'dan']
>>> list1.sort()
>>> print(list1)
['Dan', 'Ronit', 'dan']
-------------------


▲アルファベット順で並べ替え
-------------------
>>> list1 = ['Ronit', 'Dan', 'dan']
>>> list1.sort(key=str.lower)
>>> print(list1)
['Dan', 'dan', 'Ronit']
-------------------


▲キーに指定したstr.lower関数を見てみる
-------------------
>>> print(str.lower('ABC'))
abc
-------------------


▲str.upper関数を見てみる
-------------------
>>>print(str.upper('abc'))
ABC
-------------------


▲降順で並べ替え
-------------------
>>> list1 = ['1000', '10', '1', '100']
>>> list1.sort(reverse=True)
>>> print(list1)
['1000', '100', '10', '1']
-------------------


【3-5】
▲タプルのソート
-------------------
>>> tuple1 = ('abbb', 'abcc', 'aaaa', 'abcd')
>>> print(sorted(tuple1))
['aaaa', 'abbb', 'abcc', 'abcd']
>>> type(sorted(tuple1))
<class 'list'>
-------------------


▲元のリストは変更されない
-------------------
>>> list1 = ['10', '100', '1', '0']
>>> print(sorted(list1, reverse=True))
['100', '10', '1', '0']
>>> print(list1)
['10', '100', '1', '0']
-------------------


▲並び替えた結果を保持するには変数に代入しておく
-------------------
>>> list2 = sorted(list1, reverse=True)
>>> print(list2)
['100', '10', '1', '0']
-------------------