C++ 比较超载的学生<;操作人员
这是要比较的字符串,lastname+firstName和id comp是公共的,我的排序方法不起作用,我无法找到代码失败的地方,我应该按顺序列出学生C++ 比较超载的学生<;操作人员,c++,c++11,C++,C++11,这是要比较的字符串,lastname+firstName和id comp是公共的,我的排序方法不起作用,我无法找到代码失败的地方,我应该按顺序列出学生 comp=new char[strlen(lName)+strlen(fName)+strlen(id)+1]; 这是我的学生构装师: Student::Student(char * first, char * last, char *i,char * stand, int credit, double g, Date * d, Date *
comp=new char[strlen(lName)+strlen(fName)+strlen(id)+1];
这是我的学生构装师:
Student::Student(char * first, char * last, char *i,char * stand, int credit, double g, Date * d, Date * matricDate){
lName=last;
fName=first;
id=i;
standing=stand;
credits=credit;
gpa=g;
dob=d;
matDate=matricDate;
comp=new char[strlen(lName)+strlen(fName)+strlen(id)+1];
sprintf(comp,"%s%s%s",lName,fName,id);
};
我是接线员
bool Student::operator<(const Student &second){
if(comp<second.comp){
return true;
}else{
return false;
}
};
这是我喜欢的类型:
void Roster::mySort(){
sort(roster_list.begin(),roster_list.end());
};
我的主要意见是:
#include<iostream>
#include"Roster.cpp"
#include "Date.cpp"
#include "Student.cpp"
using namespace std;
int main(){
Roster *r=new Roster();
Date *d=new Date(12,05,1987);
Student *st=new Student("Jason", "Sam", "124542", "sophomore", 34, 4.0, d,d);
Student *st2=new Student("Ahmad", "Khan", "23452", "freshman", 34, 4.0, d,d);
Student *st3=new Student("Selam", "Can", "23431", "freshman", 34, 3.0, d,d);
Student *st4=new Student("Andrew", "Rosenberg", "34523", "Senior", 34, 4.0, d,d);
Student *st5=new Student("Selam", "Can", "23431", "freshman", 34, 3.0, d,d);
r->addStudent(st);
r->addStudent(st2);
r->addStudent(st3);
r->addStudent(st4);
// Student 3 and 5 are same
// == operator check
if(*st3==*st5){
cout<<"Students are same \n";
}
// != overloading operator check
if(*st3!=*st4){
cout<<"Students are different\n";
}
cout<<"################Before Sorting###############\n";
r->toString();
cout<<"################After Sorting###############\n";
r->mySort();
r->toString();
cout<<"\n"<<st->getComp();
cout<<"\n"<<st3->getComp();
return 0;
}
我试过这个
bool StudentSort(Student* lhs, Student* rhs) {
return (*lhs)<(*rhs);
}
void Roster::mySort(){
sort(roster_list.begin(),roster_list.end(),StudentSort);
};
看起来您已将
bool StudentSort
设置为花名册
的成员函数。你应该让它成为非会员
顺便说一句,你应该使你的
运算符在我看来,每个地方都有指针。我敢打赌这些都不是必需的。@chris这是上次发布此代码时指出的。但是它们比不必要更糟糕,它们实际上是OP各种问题的原因。看起来comp
只是一个字符指针。我认为比较函数需要做更多的工作才能正常工作。这让我想到==
和=代码>也比较指针,当不使用硬编码的文字字符串时,指针会很快崩溃。@RetiredInja是的,我认为整个东西都坏得很厉害。上次OP发布这篇文章时,我已经建议不要使用指针。这个建议似乎没有任何影响:/
#include<iostream>
#include"Roster.cpp"
#include "Date.cpp"
#include "Student.cpp"
using namespace std;
int main(){
Roster *r=new Roster();
Date *d=new Date(12,05,1987);
Student *st=new Student("Jason", "Sam", "124542", "sophomore", 34, 4.0, d,d);
Student *st2=new Student("Ahmad", "Khan", "23452", "freshman", 34, 4.0, d,d);
Student *st3=new Student("Selam", "Can", "23431", "freshman", 34, 3.0, d,d);
Student *st4=new Student("Andrew", "Rosenberg", "34523", "Senior", 34, 4.0, d,d);
Student *st5=new Student("Selam", "Can", "23431", "freshman", 34, 3.0, d,d);
r->addStudent(st);
r->addStudent(st2);
r->addStudent(st3);
r->addStudent(st4);
// Student 3 and 5 are same
// == operator check
if(*st3==*st5){
cout<<"Students are same \n";
}
// != overloading operator check
if(*st3!=*st4){
cout<<"Students are different\n";
}
cout<<"################Before Sorting###############\n";
r->toString();
cout<<"################After Sorting###############\n";
r->mySort();
r->toString();
cout<<"\n"<<st->getComp();
cout<<"\n"<<st3->getComp();
return 0;
}
Students are same
Students are different
################Before Sorting###############
Student Info:Jason Sam 124542 sophomore 4
Birth Date: December 5, 1987
Matric Date: December 5, 1987
Student Info:Ahmad Khan 23452 freshman 4
Birth Date: December 5, 1987
Matric Date: December 5, 1987
Student Info:Selam Can 23431 freshman 3
Birth Date: December 5, 1987
Matric Date: December 5, 1987
Student Info:Andrew Rosenberg 34523 Senior 4
Birth Date: December 5, 1987
Matric Date: December 5, 1987
################After Sorting###############
Student Info:Jason Sam 124542 sophomore 4
Birth Date: December 5, 1987
Matric Date: December 5, 1987
Student Info:Ahmad Khan 23452 freshman 4
Birth Date: December 5, 1987
Matric Date: December 5, 1987
Student Info:Selam Can 23431 freshman 3
Birth Date: December 5, 1987
Matric Date: December 5, 1987
Student Info:Andrew Rosenberg 34523 Senior 4
Birth Date: December 5, 1987
Matric Date: December 5, 1987
SamJason124542
CanSelam23431
bool StudentSort(Student* lhs, Student* rhs) {
return (*lhs)<(*rhs);
}
void Roster::mySort(){
sort(roster_list.begin(),roster_list.end(),StudentSort);
};
Roster.cpp: In member function ‘void Roster::mySort()’:
Roster.cpp:69: error: argument of type ‘bool (Roster::)(Student*, Student*)’ does not match ‘bool (Roster::*)(Student*, Student*)’
bool Student::operator<(const Student& second) const {
return comp<second.comp;
}
bool StudentSort(const Student* lhs, const Student* rhs) { .... }