! 2.6.f90
! 20140211 1.1
! $Id: 2.6.f90 1.2 2016/10/29 02:10:54 s Exp $
!
! cf : cash flow
! pv : preset value
! r  : rate
!
! main
!
implicit none
integer  j, k, n1, n2, n3, n4
real(8)  pv1, pv2, pv3, pv4, r
integer, dimension(0:100) :: i
real(8), dimension(0:100) :: cf1, cf2, cf3, cf4

! input
r = 0.12
i(0:100) = (/(k, k=0, 100)/)

n1 = 6 - 1
cf1(0:n1) = -1000.0

n2 = 6 - 1
cf2(0)   = -1000.0 - 900.0
cf2(1:n2) = -900.0

n3 = 12 - 1
cf3(0:n3) = -1000.0

n4 = 12 - 1
cf4(0)   = -1000.0 - 900.0
cf4(1:n4) = -900.0

! calculate
pv1 = sum(cf1(0:n1) / (1.0 + r / 12.0) ** i(0:n1) )
pv2 = sum(cf2(0:n2) / (1.0 + r / 12.0) ** i(0:n2))
pv3 = sum(cf3(0:n3) / (1.0 + r / 12.0) ** i(0:n3))
pv4 = sum(cf4(0:n4) / (1.0 + r / 12.0) ** i(0:n4))

! output
print *, '2.6'
print *, 'input'
print '(a5, f10.2)',   'r=', r
print '(a5, 12i7)',    'i=', (i(j), j = 0, 11)
print '(a5,(12f7.0))', 'cf1= ', (cf1(j), j = 0, n1)
print '(a5,(12f7.0))', 'cf2= ', (cf2(j), j = 0, n2)
print '(a5,(12f7.0))', 'cf3= ', (cf3(j), j = 0, n3)
print '(a5,(12f7.0))', 'cf4= ', (cf4(j), j = 0, n4)
print *, 'output'
print '(a10, i10)', 'pv1($) = ', int(pv1)
print '(a10, i10)', 'pv2($) = ', int(pv2)
print '(a10, i10)', 'pv3($) = ', int(pv3)
print '(a10, i10)', 'pv4($) = ', int(pv4)

stop
end
! end of 2.6.f90 
!
! below is output
!
!2.6
! input
!   r=      0.12
!   i=      0      1      2      3      4      5      6      7      8      9     10     11
!cf1=  -1000. -1000. -1000. -1000. -1000. -1000.
!cf2=  -1900.  -900.  -900.  -900.  -900.  -900.
!cf3=  -1000. -1000. -1000. -1000. -1000. -1000. -1000. -1000. -1000. -1000. -1000. -1000.
!cf4=  -1900.  -900.  -900.  -900.  -900.  -900.  -900.  -900.  -900.  -900.  -900.  -900.
! output
! pv1($) =      -5853
! pv2($) =      -6268
! pv3($) =     -11367
! pv4($) =     -11230