Question

我是一名c ++初学者，对以下代码有一个理解问题。

#include <iostream>
using namespace std;

struct  student {

    string name;

    int age;

    float marks;

};

struct student *initiateStudent(string , int , float );
struct student *highestScorer(student **, int);

int main ( ) {

int totalStudents = 1;

string name;

int age;

float marks;

cin >> totalStudents;

student *stud[totalStudents];

for( int i = 0; i < totalStudents; i++ )  {

cin >> name >> age >> marks;

stud[i] = initiateStudent(name,age,marks);

}


student *topper = highestScorer(stud,totalStudents);


cout << topper->name << " is the topper with " << topper->marks << " marks" << endl;

for (int i = 0; i < totalStudents; ++i)
{
   delete stud[i];
}

return 0;

}

struct student *initiateStudent(string name, int age, float marks)
{
   student *temp_student;
   temp_student = new student;
   temp_student->name  = name;
   temp_student->age   = age;
   temp_student->marks = marks;
   return temp_student;
}


struct student *highestScorer( student **stud, int totalStudents)
{
   student *temp_student;
   temp_student = new student;
   temp_student = stud[0];
   for (int i = 1; i < totalStudents; ++i)
   {
      if (stud[i]->marks > temp_student->marks)
      {
         temp_student = stud[i];
      }
   }

   return temp_student;
}

代码工作正常，但我不明白为什么我需要声明函数 struct student * highestScorer（student **，int）; 用**即双指针传递指针只用一个初始化。

我会用一个*声明函数，因为那是我要传递的变量类型？

非常感谢。

Answer 1

因为stud中的main变量是一个student指针数组。当您通过参数传递数组时，您需要一个指向第一个元素的指针，无论元素是什么。由于数组是一个指针数组，因此你有一个指向指针的指针。

理解双指针问题并将它们传递给函数

1 个答案: