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enumerateで要素ごとのインデックスを表示しよう

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iteratableなオブジェクト(list, tupleなど)の要素ごとのインデックスを表示するにはenumerateが便利です。

enumerate

どう便利かと言うと例えばこんな感じのデータ達に対して

対象データ
names = ["Suzuki", "Tanaka", "Kato", "Suzuki", "Kato"]

わざわざ数え上げするためだけの変数counterを用意せずとも

変数counterを使う方法
counter = 0
for name in names:
    print(counter, name)
    counter += 1
"""
0 Suzuki
1 Tanaka
2 Kato
3 Suzuki
4 Kato
"""

enumerateを使えばもっとスッキリ書けます。

enumerateを使う方法
for counter, name in enumerate(names):
    print(counter, name)
"""
0 Suzuki
1 Tanaka
2 Kato
3 Suzuki
4 Kato
"""

以上です、お疲れ様でした。

 参考

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