Return true if the card number is valid
bool isValid ( long int number ) { return ( getSize ( number ) >= 13 && getSize ( number ) <= 16 ) && ( prefixMatched ( number , 4 ) || prefixMatched ( number , 5 ) || prefixMatched ( number , 37 ) || prefixMatched ( number , 6 ) ) && ( ( sumOfDoubleEvenPlace ( number ) + sumOfOddPlace ( number ) ) % 10 == 0 ) ; }