#include<stdio.h>

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

void swap(struct student *, struct student *);

void main()
{
    struct student s[3];
    struct student *ptr = NULL;

    int i, j;
    ptr = s;

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

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

    ptr = s;

    printf("\nAfter sorting students by roll no..\n");
    for(i=0; i<3; i++)
    {
        printf("\n%d   %10s  %10s", ptr->rollno, ptr->name, ptr->branch);
        ptr++;
    }
    getch();
}

void swap(struct student *a, struct student *b)
{
    struct student temp;

    temp = *a;
    *a = *b;
    *b = temp;
}