Passing array of objects as parameter in C++

Array of Objects:It is an array whose elements are of the class type. It can be declared as an array of any datatype.

Syntax:

classname array_name [size];

Below is the C++ program to illustrate the array of objects by calculating the highest marks among 3 students:

// C++ program to illustrate the // passing the array of objects // to function parameter #include <bits/stdc++.h> using namespace std; // Class Student class Student {  int roll;  char name[50];  int total; public:  // Function to input Roll Number  void getdata()  {  cout << "Enter your Roll: "  << endl;  cin >> roll;  cout << "Enter your Name: "  << endl;  cin.ignore();  cin.get(name, 50);  cout << "Enter your Total "  << "Marks: " << endl;  cin >> total;  }  // Function to pass the array of  // objects  int pos(Student obj[], int size)  {  int pos = 0;  int max = obj[0].total;  // Traverse the array of object  for (int i = 0; i < size; i++) {  if (obj[i].total > max) {  max = obj[i].total;  pos = i;  }  }  return pos;  }  // Function to display the students  // details  void putdata()  {  cout << "Roll: " << roll  << endl;  cout << "Name: " << name  << endl;  cout << "Total Marks: "  << total << endl;  } }; // Function that have array of objects void arrayOfObjects() {  Student s[3], s1;  int pos;  for (int i = 0; i < 3; i++) {  s[i].getdata();  }  pos = s1.pos(s, 3);  cout << "Highest scoring Student"  << " Details:" << endl;  s[pos].putdata(); } // Driver Code int main() {  // Function Call  arrayOfObjects();  return 0; } 

Output:

Explanation:

• In the main() function, objects of the Student class are created:
  • Here, the first array of objects is s[3] and the other one is s1(a simple object).
  • In the for loop, 3 sets of user input have been taken, (i.e, it is where the user will be entering the name, roll, total marks, for 3 students sets).
  • Then passing the s[3] (array of an object which contains the sets of student details) and its size, through the s1 object in the pos(Student obj [], int size) member function.
• The pos(Student obj [], int size) function, is returning the position of the object of the highest total marks scoring student set, i.e, (0, 1or 2 index position of s[3] object array), which is stored in pos = s1.pos(s, 3).
• Display part: For calling the display function, S[pos].putdata() is used.
  • The putdata() function is displaying the object details of the student class.
  • Here, pos is sent (which stores the index position of the highest student set object) in s, to display the highest total marks scored student details.

Time Complexity: O(n)
Auxiliary Space: O(n)