* Prime program

      integer p,a,i,j1,j2,t1
      print *,' '
      print *,'FINDS THE PRIMES BETWEEN TWO NUMBERS.'
 45   continue      
      print *,'Number x1: '
      read*,j1
      
      if (0.ge.j1) then
      goto 45
      end if

 44   continue
      print *,'Number x2 (>x1): '
      read*,j2
      
      if (j1.ge.j2) then
      goto 44
      end if
      
      do a=j1,j2

      p=1                
                            
      do i=2,(int(a**0.5))
       if (mod(a,i).eq.0) then 
        p=0
        goto 10
       end if 
      end do
 
 10   continue
        
      if (p.eq.1) then 
       print *,a,' is prime ++++++++++++++'
      else 
       print *,a,' is not prime'
      end if
      
      t1=t1+1
      if (mod(t1,22).eq.0) then
      print *,'Press ENTER for continue...'
      read*
      print *,'-----------------------------------------------------'
      end if
      
      end do  
      
      end