Ciel Numbers II
Recently, chef Ciel often hears about lucky numbers. Everybody knows that lucky numbers are positive integers whose decimal representation contains only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not. Ciel decides to make Ciel numbers. As you know, Ciel likes the digit 8 very much. And then, Ciel likes the digits 5 and 3. So Ciel defines Ciel numbers a
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solution.cppC++17
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