小编Spe*_*ber的帖子

码:

SchedulingItem operator[](Schedule obj,int el){
    return obj.OfVector().at(el);
}

错误:

academia::SchedulingItem academia::operator[](academia::Schedule, int)' must be a nonstatic member function
     SchedulingItem operator[](Schedule obj,int el)

问题出在哪儿？