Array of Structure

#include<iostream>
using namespace std;
struct student{                      /*declaring the structure*/
                 int rollno;
                 char name[30];
                 char std[5];
              };
int main()
{
    student su[50];
    int n;
    cout<<"Enter how many students to feed data : ";
    cin>>n;
    cout<<"\n\n";
    for(int i=0;i<n;++i)//input for the structure
    {
        cout<<"Enter details of student "<<i+1<<"\n\n";
        cout<<"Enter Roll NO. : ";
        cin>>su[i].rollno;
        fflush(stdin);
        cout<<"Enter Name : ";
        cin.getline(su[i].name,28);
        cout<<"Enter Class : ";
        cin.getline(su[i].std,5);
    }
    cout<<"\n\n";
    cout<<"Details about students are as follows :---\n\n";
    for(int i=0;i<n;++i)//displaying
    {
         cout<<"\nRoll NO. : "<<su[i].rollno;
         cout<<"\nName : "<<su[i].name;
         cout<<"\nClass : "<<su[i].std;
    }
    return 0;
}