string timeConversion(string s) {

int nDigits = 2;

auto time = s.substr(0, s.size() - nDigits);
auto zone = s.substr(s.size() - nDigits);
int hour = stoi(time.substr(0, nDigits));

std::stringstream ss;
ss << std::setw(nDigits) << std::setfill('0');
    
if(zone == "AM"){
    auto amHour = hour%12;

    ss << amHour << time.substr(nDigits);
}
else{
    
    auto pmHour = hour;
    
    if(hour < 12){
        pmHour = hour + 12;
    }

    ss << pmHour << time.substr(nDigits);
}

return ss.str();
}