The document contains a C++ program that defines a Student class and allows users to input a roll number to display the student’s details, including name, subject marks, percentage, and grade. Each student's information is presented through a switch-case structure based on the input roll number, with details for up to 20 students. The program aims to illustrate basic concepts of object-oriented programming and user interaction in C++.

1. #include<iostream>
using namespace std;
class Student
{
private:
double rollno;
public:
void setroll(int a);
int showroll();
Student():rollno(0)
{
}
Student(int a):rollno(a)
{
}
void search_roll();
};
void Student::setroll(int a)
{
rollno=a;
}
int Student::showroll()
{
return rollno;
}
void Student:: search_roll()
{
int r;
Student d;
cout<<"Enter Roll No :";
cin>>r;
d.setroll(r);
switch(r)
{
case 1:
{
cout<<"==========================================n";
cout<<"nRoll number of student :1 ";
cout<<"nName of student :Mobeenn";
cout<<"nMarks in Physics :60/100n
";
cout<<"nMarks in Chemistry :70/100n ";
cout<<"nMarks in Maths : 80/100n";
cout<<"nMarks in English :85/100n ";
cout<<"nMarks in Computer Science :65/100n";
cout<<"nPercentage of student is : 72%n";
cout<<"nGrade of student is :Bn";
cout<<"==========================================n";
break;
}
case 2:
{
cout<<"==========================================n";

2. cout<<"nRoll number of student :2 ";
cout<<"nName of student :Kashifn";
cout<<"nMarks in Physics :70/100n ";
cout<<"nMarks in Chemistry :80/100n ";
cout<<"nMarks in Maths :90/100n";
cout<<"nMarks in English :76/100n ";
cout<<"nMarks in Computer Science :57/100n";
cout<<"nPercentage of student is :74%n";
cout<<"nGrade of student is :Bn";
cout<<"==========================================n";
break;
}
case 3:
{
cout<<"==========================================n";
cout<<"nRoll number of student :3 ";
cout<<"nName of student :Qamarn";
cout<<"nMarks in Physics :75/100n
";
cout<<"nMarks in Chemistry :85/100n ";
cout<<"nMarks in Maths :72/100n";
cout<<"nMarks in English :76/100n ";
cout<<"nMarks in Computer Science :87/100n";
cout<<"nPercentage of student is : 79%n";
cout<<"nGrade of student is :Bn";
cout<<"==========================================n";
break;
}
case 4:
{
cout<<"==========================================n";
cout<<"nRoll number of student :4 ";
cout<<"nName of student :Alin";
cout<<"nMarks in Physics :80/100n ";
cout<<"nMarks in Chemistry :52/100n ";
cout<<"nMarks in Maths :48/100n";
cout<<"nMarks in English :35/100n ";
cout<<"nMarks in Computer Science :78/100n";
cout<<"nPercentage of student is : 59%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 5:
{
cout<<"==========================================n";
cout<<"nRoll number of student :5 ";
cout<<"nName of student :Husnain Alin";
cout<<"nMarks in Physics :70/100n ";
cout<<"nMarks in Chemistry :52/100n ";
cout<<"nMarks in Maths :58/100n";
cout<<"nMarks in English :75/100n ";
cout<<"nMarks in Computer Science :78/100n";
cout<<"nPercentage of student is :66%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 6:
{
cout<<"==========================================n";

3. cout<<"nRoll number of student :6 ";
cout<<"nName of student :Adnan alin";
cout<<"nMarks in Physics :50/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 62%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 7:
{
cout<<"==========================================n";
cout<<"nRoll number of student :7 ";
cout<<"nName of student :Mohsin Alin";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :88/100n ";
cout<<"nMarks in Computer Science :79/100n";
cout<<"nPercentage of student is :71%n";
cout<<"nGrade of student is :Bn";
cout<<"==========================================n";
break;
}
case 8:
{
cout<<"==========================================n";
cout<<"nRoll number of student :8 ";
cout<<"nName of student :Hamza Alin";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 9:
{
cout<<"==========================================n";
cout<<"nRoll number of student :9 ";
cout<<"nName of student :Hamza Farooqn";
cout<<"nMarks in Physics :56/100n ";
cout<<"nMarks in Chemistry :75/100n ";
cout<<"nMarks in Maths :85/100n";
cout<<"nMarks in English :56/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 69%n";
cout<<"nGrade of student is :Bn";
cout<<"==========================================n";
break;
}
case 10:
{
cout<<"==========================================n";
cout<<"nRoll number of student :9 ";
cout<<"nName of student :Hassan Alin";
cout<<"nMarks in Physics :59/100n ";
cout<<"nMarks in Chemistry :45/100n ";

4. cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :85/100n ";
cout<<"nMarks in Computer Science :35/100n";
cout<<"nPercentage of student is : 60%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 20:
{
cout<<"==========================================n";
cout<<"nRoll number of student :20 ";
cout<<"nName of student :Junaid Alin";
cout<<"nMarks in Physics :56/100n ";
cout<<"nMarks in Chemistry :75/100n ";
cout<<"nMarks in Maths :35/100n";
cout<<"nMarks in English :95/100n ";
cout<<"nMarks in Computer Science :85/100n";
cout<<"nPercentage of student is : 69%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 11:
{
cout<<"==========================================n";
cout<<"nRoll number of student :11 ";
cout<<"nName of student :Salman Ahmad Alin";
cout<<"nMarks in Physics :45/100n ";
cout<<"nMarks in Chemistry :35/100n ";
cout<<"nMarks in Maths :71/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :45/100n";
cout<<"nPercentage of student is : 52%n";
cout<<"nGrade of student is :Dn";
cout<<"==========================================n";
break;
}
case 12:
{
cout<<"==========================================n";
cout<<"nRoll number of student :12 ";
cout<<"nName of student :Abdulwahab n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 13:
{
cout<<"==========================================n";
cout<<"nRoll number of student :13 ";
cout<<"nName of student :Aslam Ali n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";

5. cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 14:
{
cout<<"==========================================n";
cout<<"nRoll number of student :14 ";
cout<<"nName of student :Mudassir Ali n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 15:
{
cout<<"==========================================n";
cout<<"nRoll number of student :15 ";
cout<<"nName of student :Anas Rafique n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 16:
{
cout<<"==========================================n";
cout<<"nRoll number of student :16 ";
cout<<"nName of student :Zain Ali n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 19:
{
cout<<"==========================================n";
cout<<"nRoll number of student :19 ";
cout<<"nName of student :Sohail Ahmad n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}

6. case 17:
{
cout<<"==========================================n";
cout<<"nRoll number of student :17 ";
cout<<"nName of student :Dawood Hameed n";
cout<<"nMarks in Physics :75/100n ";
cout<<"nMarks in Chemistry :35/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :15/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 18:
{
cout<<"==========================================n";
cout<<"nRoll number of student :19 ";
cout<<"nName of student :Ahmad Ali n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
default:
{
cout<<"Invalid Roll number Try again";
}
}
}
int main()
{
Student a;
a.search_roll();
return 0;
}

7. case 17:
{
cout<<"==========================================n";
cout<<"nRoll number of student :17 ";
cout<<"nName of student :Dawood Hameed n";
cout<<"nMarks in Physics :75/100n ";
cout<<"nMarks in Chemistry :35/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :15/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
case 18:
{
cout<<"==========================================n";
cout<<"nRoll number of student :19 ";
cout<<"nName of student :Ahmad Ali n";
cout<<"nMarks in Physics :66/100n ";
cout<<"nMarks in Chemistry :45/100n ";
cout<<"nMarks in Maths :75/100n";
cout<<"nMarks in English :65/100n ";
cout<<"nMarks in Computer Science :75/100n";
cout<<"nPercentage of student is : 65%n";
cout<<"nGrade of student is :Cn";
cout<<"==========================================n";
break;
}
default:
{
cout<<"Invalid Roll number Try again";
}
}
}
int main()
{
Student a;
a.search_roll();
return 0;
}