NEB28:program to sort records using struct

//program to sort records using struct from a to z
#include<stdio.h>
#include<conio.h>
struct detail
{
int roll;
char name[100];
char address[100];
}var[100],temp;

void main()
{
int i,j,n;
printf("enter total records (less or than '100')\n");
scanf("%d",&n);
printf("now enter records of students\n");
for(i=0;i<n;i++)
{
printf("enter student's roll no.\n");
scanf("%d",&var[i].roll);
printf("enter student's name\n");
scanf("%s",var[i].name);
printf("enter student's address\n");
scanf("%s",var[i].address);
}
printf("now sorting from a to z on the basis of  address\n");
for(i=0;i<n;i++)
 {
     for(j=i+1;j<n;j++)
       {
            if((strcmp(var[i].address,var[j].address))>0)
                  {
                      temp=var[i];
                      var[i]=var[j];
                     var[j]=temp;
                   }
         }
}
printf("sorted data (from a to z i.e. ascending order )on the basis of address are:\n:");
  for(i=0;i<n;i++)
{
printf("student's roll=%d, name=%s,student's address=%s \n",var[i].roll,var[i].name,var[i].address);
}
getch();
}
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//program to sort records using struct(in descending order i.e. z to a)
#include<stdio.h>
#include<conio.h>
struct detail
{
int roll;
char name[100];
char address[100];
}var[100],temp;

void main()
{
int i,j,n;
printf("enter total records (less or than '100')\n");
scanf("%d",&n);
printf("now enter records of students\n");
for(i=0;i<n;i++)
{
printf("enter student's roll no.\n");
scanf("%d",&var[i].roll);
printf("enter student's name\n");
scanf("%s",var[i].name);
printf("enter student's address\n");
scanf("%s",var[i].address);
}
printf("now sorted data (z to a) on the basis of address are:\n:);
for(i=0;i<n;i++)
 {
     for(j=i+1;j<n;j++)
       {
            if((strcmp(var[i].address,var[j].address))<0)
                  {
                      temp=var[i];
                      var[i]=var[j];
                     var[j]=temp;
                   }
         }
}
  for(i=0;i<n;i++)
{
printf("student's roll=%d, name=%s,student's address=%s \n",var[i].roll,var[i].name,var[i].address);
}

getch();

}

--------------------------------------------------------------------------------

note:

Here I have done both, from 'a' to 'z' and 'z' to 'a'. You can do only one, either 'a' to 'z' or 'z' to 'a'. 

NEB30:Difference between struct and union

Ans:-
The differences between struct and union are given below in tabular form.
                   

struct	Union
1.It stores dis-similar data.Each gets separate space in memory.They do not share memory	1. It stores dis-similar type of data.Total memory space is equal to the member with largest size.They share memory space.
2.we can access member in any sequence .	2.We can access that whose value is recently used.
3.It uses keyword 'struct'	3.It uses keyword 'union'
4.We can initialize values of member/s and in any order	4.We can initialize that member which is first declared.
5.It consumes more memory	5.It consumes less memory.
6.Its syntax     struct tag { datatype member1; datatype member2; datatype member3; }variable;	6.Its syntax     union tag { datatype member1; datatype member2; datatype member3; }variable;
Example struct student { int roll; char sex; float percentage; }var;	Example union student { int roll; char sex; float percentage; }var;

NEB27:program to get factorial value of a number using recursion

//program to get factorial value of a number using recursion
#include <stdio.h>
#include <stdlib.h>
int recur(int n);
int main()
{
 int n;
 printf("ente a number\n");
 scanf("%d",&n);
printf("the factorial value is\n");
printf("%d",recur(n));
getch();
return 0;
}
int recur(int n)
{
 if(n<=0)
  {
          return 1;
}
else
{
    return n*recur(n-1);
}

}