c++ - Age output not calculating -

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• what special numbers starting zero? 4 answers

patientdemographicinformation patientjones("123456789", "jones",                                                'a', "mary",                                                "mc donalds department, 555 elm street, apt 2,                                                "666 west side",                                                "san diego", "ca", "76032", "3899",                                                "360", "89054392012",                                                'f', 02031934);  patientjones.printpatientdemographicinformation();  int patientdemographicinformation::getpatientage( ) {          time_t t = time(0);   // time        struct tm * = localtime( & t );        int yearnow = (now->tm_year + 1900);        int birthyear  =  (patientdateofbirth % 10000);         return yearnow - birthyear;   } 

main.cpp:27:50: error: invalid digit "9" in octal constant <-- error...

it not calculate years months , days. used 11171993 birth date , worked. although, need birth date of 02031934 , genuinely date work. welcome.

thank you!

according this reference, beginning of integer constant 0, in 01011967, indicates octal notation, consequently makes impossible use 9 in constant.