Prime Numbers between two given numbers ( C Program )

Non-Recursive Program:

Aim: To print Prime numbers between given two numbers.

Program:
#include<stdio.h>
#include<conio.h>
void main()
{
  int fnum,lnum,i,j,flag=0;
printf("Enter First Number:\n");
scant("%d",&fnum);
printf("Enter Last Number:\n");
scant("%d",&lnum);
  if(lnum<2)
{
printf("There are no primes upto %d\n",lnum);
exit(0);
}
printf("Prime Numbers between %d and %d are:\n",fnum,lnum);
for(i=fnum;i<=lnum;i++)
  {
    for(j=2;j<i/2;j++)
      {
         if(i%j==0)
            {
                flag=1;
                break;
             }
       }
      if(flag==0)
      printf("\t%d",i);
   }

Output:
Enter First Number: 10
Enter Last Number:  20
Prime Numbers between 10 and 20 are: 11 13  17  19

Click here to know programs list in this blog