SUPER LUCKY PALLINDROME

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Lucky numbers are positive integers composed only of the digits ‘4’ and ‘7’. For example, 47477 and 777 are lucky numbers while 457 and 1232 are not. Super lucky numbers have the following additional properties: • They are a lucky number themselves • Number of digits in them is a lucky number • The number of ‘4’s or the number of ‘7’s in them is a lucky number (or both counts are lucky numbers

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solution.cppC++17

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