(key, value)ペアのリストが与えられたら、それが関数を表すかどうか、つまり各キーが一貫した値にマップされるかどうかを判断します。つまり、2つのエントリのキーが等しい場合は、値も同じである必要があります。繰り返し入力しても問題ありません。
例えば：
# Not a function: 3 maps to both 1 and 6
[(3,1), (2,5), (3,6)]
# Function: It's OK that (3,5) is listed twice, and that both 6 and 4 both map to 4
[(3,5), (3,5), (6,4), (4,4)]
入力：(key, value) 1〜9の数字を使用したペアの順序付きシーケンス。特定の順序付けは不要です。または、キーリストと値リストを別々の入力として使用することもできます。
出力：機能の一貫した値、および機能以外の一貫した値。
テストケース：最初の5つの入力は関数であり、最後の5つの入力は関数ではありません。
[(3, 5), (3, 5), (6, 4), (4, 4)]
[(9, 4), (1, 4), (2, 4)]
[]
[(1, 1)]
[(1, 2), (2, 1)]
[(3, 1), (2, 5), (3, 6)]
[(1, 2), (2, 1), (5, 2), (1, 2), (2, 5)]
[(8, 8), (8, 8), (8, 9), (8, 9)]
[(1, 2), (1, 3), (1, 4)]
[(1, 2), (1, 3), (2, 3), (2, 4)]
ここでは、入力の2つのリストとして示します。
[[(3, 5), (3, 5), (6, 4), (4, 4)], [(9, 4), (1, 4), (2, 4)], [], [(1, 1)], [(1, 2), (2, 1)]]
[[(3, 1), (2, 5), (3, 6)], [(1, 2), (2, 1), (5, 2), (1, 2), (2, 5)], [(8, 8), (8, 8), (8, 9), (8, 9)], [(1, 2), (1, 3), (1, 4)], [(1, 2), (1, 3), (2, 3), (2, 4)]]
リーダーボード：
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body{text-align:left!important}#answer-list,#language-list{padding:10px;width:290px;float:left}table thead{font-weight:700}table td{padding:5px}
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