#include<string.h>

struct student
{
    int rollno;
    char name[10];
    char branch[10];
};

void main()
{
    struct student s[3], t;
    int i, j;

    for(i=0; i<3; i++){
        printf("Enter details of Student# %d\n",i+1);
        printf("Enter roll no: ");
        scanf("%d", &s[i].rollno);
        printf("Enter name: ");
        scanf("%s", s[i].name);
        printf("Enter branch: ");
        scanf("%s", s[i].branch);
    }

    for(i=0; i<3; i++)
    {
        for(j=0; j<2; j++)
        {
            if(s[j].rollno > s[j+1].rollno)
            {
                t.rollno = s[j].rollno;
                s[j].rollno = s[j+1].rollno;
                s[j+1].rollno = t.rollno;

                strcpy(t.name, s[j].name);
                strcpy(s[j].name, s[j+1].name);
                strcpy(s[j+1].name, t.name);

                strcpy(t.branch, s[j].branch);
                strcpy(s[j].branch, s[j+1].branch);
                strcpy(s[j+1].branch, t.branch);
            }
        }
    }

    printf("After sorting students by roll no..\n");
    for(i=0; i<3; i++)
    {
        printf("\n%d   %10s  %10s", s[i].rollno, s[i].name, s[i].branch);
    }
    getch();
}
/* OUTPUT
Enter details of Student# 1
Enter roll no: 3
Enter name: Harsh
Enter branch: CO
Enter details of Student# 2
Enter roll no: 2
Enter name: Sudhir
Enter branch: IT
Enter details of Student# 3
Enter roll no: 1
Enter name: Laksham
Enter branch: CO

After sorting students by roll no..

1      Laksham          CO
2       Sudhir          IT
3        Harsh          CO
*/