7. Design a C++ base class consisting of the data members such as name of the student, roll number and subject. The derived class consists of the data members subject code, internal assessment and university examination marks. Construct a virtual base class for the item name of the student and roll number. The program should have the facilities. i) Build a master table ii) List a table iii) Insert a new entry iv) Delete old entry v) Edit an entry vi) Search for a record

//Program Code

#include<iostream>
#include<stdlib.h>
#include<string.h>
#include<iomanip>

using namespace std;
static int cnt;
class stud
{
 public:
 char name[20];
 int roll;
};
class s2 : public virtual stud
{
 public : char sub[10];
    int scode;
    int sem;
    char div[2];
};
class s1:virtual public stud
{
public : char addr[30];
    int pin;
};
class sdata:public s1,public s2
{
 public : int subc1;
          int im1;
          int um1;
};

int main()
{
  sdata m[100];
  char c='y',str2[10];
  int op,n,i,j,flag=0,rl,r;
  do
  { 
    cout<<"\n * * * * * * Menu  * * * * * *";
    cout<<"\n 1. Build Table \n 2. List a Table \n 3. insert new entry";
    cout<<"\n 4. Delete an entry \n 5. Edit an entry \n 6. Search for record \n Enter your choice :";
    cin>>op;
    switch(op)
     {
       case 1 : cout<<"\n building new Table";
        cout<<"\n Enter total number of Entries :";
                cin>>n;
                for(i=0;i<n;i++)
                {
         cout<<"\n Enter Name of Student :";
                cin>>m[i].name;
        cout<<"\n Enter Roll number     :";
                cin>>m[i].roll;
        cout<<"\n Enter Name of Subject :";
                cin>>m[i].sub;
        cout<<"\n Enter Subject code for Subject "<<m[i].sub<<":";
                cin>>m[i].scode;
        cout<<"\n Enter internal marks for Subject "<<m[i].sub<<":";
                cin>>m[i].im1;
        cout<<"\n Enter University exam marks for Subject "<<m[i].sub<<" :";
                cin>>m[i].um1;
        cnt++;
                 }//for
                break;
       case 2 : cout<<"\n Entries in Table are :";
        cout<<setw(20)<<"\n Name_of_Student"<<setw(8)<<"Roll No"<<setw(12)<<"Subject"<<setw(10)<<"Sub_code"<<setw(12)<<"Internal"<<setw(12)<<"External";   
        cout<<"\n----------------------------------------------------------------------------------------";
        for(i=0;i<cnt;i++)
        {
       
cout<<endl<<setw(10)<<m[i].name<<setw(10)<<m[i].roll<<setw(12)<<m[i].sub<<setw(10)<<m[i].scode<<setw(12)<<m[i].im1<<setw(12)<<m[i].um1;       
        }
        break;
    case 3:j=cnt;
        cout<<"\n Enter Name of Student :";
                cin>>m[j].name;
        cout<<"\n Enter Roll number     :";
                cin>>m[j].roll;
        cout<<"\n Enter Name of Subject :";
                cin>>m[j].sub;
        cout<<"\n Enter Subject code for Subject "<<m[j].sub<<":";
                cin>>m[j].scode;
        cout<<"\n Enter internal marks for Subject "<<m[j].sub<<":";
                cin>>m[j].im1;
        cout<<"\n Enter University exam marks for Subject "<<m[j].sub<<" :";
                cin>>m[j].um1;
        cnt++;
                 break;
     case 4: cout<<"\n Enter record number to delete :";
            cin>>r;
        if(r>0 && r<=cnt)
        {
        j=r-1;
        for(i=j;i<cnt-1;i++)
        {
        m[i]=m[i+1];
          }//for
        cnt--;
        cout<<"\n Record Deleted Successfully ";       
        }//if
        else
            cout<<"\n Entered wrong record number,please enter correct record number \n";   
        break;

    case 5: cout<<"\n Enter record number to edit :";
            cin>>r;
        if(r>0 && r<=cnt) {
        j=r-1;
        cout<<"\n Select Field to Edit : 1. Name \n 2. Roll Number \n 3. Subject Name \n4.Subject code \n5. Internal Marks  \n6. Universirt Exam marks  \n Choice : ";
        cin>>op;
        switch(op)
        {
        case 1 : cout<<"\n Enter New Name of student :";
        cin>>m[j].name;
        break;   

        case 2 : cout<<"\n Enter updated Roll Number of student :";
        cin>>m[j].roll;
        break;
        case 3 :cout<<"\n Enter New Name of Subject :";
                cin>>m[j].sub;
        break;
       
        case 4 : cout<<"\n Enter updated Subject code for Subject "<<m[j].sub<<":";
                cin>>m[j].scode;
        break;
        case 5 : cout<<"\n Enter updated internal marks for Subject "<<m[j].sub<<":";
                cin>>m[j].im1;
        break;
       
        case 6 : cout<<"\n Enter Updated University exam marks for Subject "<<m[j].sub<<" :";
                cin>>m[j].um1;   
        break;       
           }//switch
        }//if
        else
        cout<<"\n Entered wrong record number,please enter correct record number \n";
        break;
    case 6: cout<<"\n Select data type to search :\n 1. Name \n 2.Roll Number \n Choice :";
        cin>>op;
        switch(op)
        {
        case 1:cout<<"\n Enter Name to search in table :";
            cin>>str2;
            flag=0;
            for(i=0;i<cnt;i++)
            {
            if(strcmp(m[i].name,str2)==0)
            {
              flag=1;
              cout<<"\nRecord found for name "<<str2<<". Details are : ";
              cout<<"\n Name    :"<<str2<<"\t Roll :"<<m[i].roll;
              cout<<"\n Subject :"<<m[i].sub<<"\t Subject Code :"<<m[i].scode;   
               cout<<"\n Internal:"<<m[i].im1<<"\t External :"<<m[i].um1;
              }
            else
                continue;
            }//for ends
            if(flag==0)
                cout<<"\n No record found";       
            break;
        case 2 : cout<<"\n Enter roll number to search in table :";
            cin>>rl;
            flag=0;
            for(i=0;i<cnt;i++)
            {
            if(m[i].roll==rl)
            {
              flag=1;
              cout<<"\nRecord found for Roll number "<<rl<<". Details are : ";
              cout<<"\n Name    :"<<m[i].name<<"\t Roll :"<<rl;
              cout<<"\n Subject :"<<m[i].sub<<"\t Subject Code :"<<m[i].scode;   
               cout<<"\n Internal:"<<m[i].im1<<"\t External :"<<m[i].um1;
              }
            else
                continue;
            }//for ends
            if(flag==0)
                cout<<"\n No record found";
        } //switch
        break;
      } //switch completed
   cout<<"\n Do you want to continue (y/n) ? : ";
   cin>>c;
  } while(c=='y'||c=='Y');
cout<<"********** !!! HAVE A GREAT DAY !!!************ \n";
} // program exit