我想知道这两种写法的不同，哪个是可以通过，为什么？？

第一种：

istream &operator>>(istream &stream, Advertisement &ad)
{
string temp;
Date d,m;
int t;
stream>>temp;
ad.setTitle(temp);
stream>>temp;
ad.setEmail(temp);
stream>>t;
ad.setQuantity(t);

stream>>d;
ad.setStart(d);

stream>>m;
ad.setClose(m);

stream>>temp;
ad.setBody(temp);
return stream;

}

第二种：

istream &operator>>(istream &stream, Advertisement &ad)
{
char c[100];
string n;

stream.getline(c,100);
n=c;
ad.setTitle(n);

stream.getline(c,100);
n=c;
ad.setEmail(n);

int quantity;
stream>>quantity;
ad.setQuantity(quantity);

Date start;
stream>>start;
ad.setStart(start);

Date close;
stream>>close;
ad.setClose(close);
stream.getline(c,100);
stream.getline(c,100);
n=c;
ad.setBody(n);

return stream;
}
求大侠帮忙。。。。。。。。。