program rw
implicit none
character(128):: h(10),fn1,fn2,c1,c2
real(16), parameter:: pi26=3.1415926535897932384626434_16 
real(16), parameter:: e26= 2.7182818284590452353602875_16
integer(8):: N,p,kr
real(16):: x1,x2,t1,t2,d1,d2,ref
integer:: i,j,k,l,m
character(3):: prec(3),sk

 prec(1)="32_"
 prec(2)="64_"
 prec(3)="80_"
 
 h(1)="cluster"
 h(2)="cluster42"
 
! E-test 
ref=e26
 do j=1,1 !computers
   do i=1,3  !precision
     do k=1,8 !no. of sample
        write(sk,'(i2)') k
        fn1= "./data/"//prec(i)//trim(h(j))//"_e.o2."//trim(adjustl(sk))
        print*, fn1
        fn2= prec(i)//trim(h(j))//"_E.o2"
        open(1,file=fn1,status='old')
        open(2,file=fn2)
! read and skip first 3 lines
          do l=1,3
            read(1,'(a)') c1
 !     write(2,*) c1
          end do
! write header
write(2,21)'# p','N = 2**p','type','E(seq)','(E-Eref)/Eref','time(seq)','E(par)','(E-Eref)/Eref','time(par)'
        do !read end of the file
          read(1,*,end=11) p,N,kr,x1,t1,x2,t2
            d1=(x1-ref)/ref
            d2=(x2-ref)/ref
          write(2,22) p,N,kr,x1,d1,t1,x2,d2,t2
        enddo
11     continue
       close(1)
       close(2)
    enddo !k
  enddo !i
enddo !j

21  format(a3,a15,a6,2(a24,a16,a15))
22  format(i3,i15,i4,2(f26.21,e16.6,e15.6))

end program