class Dates {
int year,month,day;
Dates(int x,int y,int z){
year=x;
month=y;
day=z;
}
public static int compare(Dates a){
return year>a.year?1
:year<a.year?-1
:month>a.month?1
:month<a.month?-1
:day>a.day?1
:day<a.day?-1:0;
}请问后面的那个三目运算符是怎么计算的啊