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! Copyright 2019-2024 Free Software Foundation, Inc.
!
! This program is free software; you can redistribute it and/or modify
! it under the terms of the GNU General Public License as published by
! the Free Software Foundation; either version 3 of the License, or
! (at your option) any later version.
!
! This program is distributed in the hope that it will be useful,
! but WITHOUT ANY WARRANTY; without even the implied warranty of
! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
! GNU General Public License for more details.
!
! You should have received a copy of the GNU General Public License
! along with this program. If not, see <http://www.gnu.org/licenses/>.
program pointers
type :: two
integer, allocatable :: ivla1 (:)
integer, allocatable :: ivla2 (:, :)
end type two
type :: typeWithPointer
integer i
type(typeWithPointer), pointer:: p
end type typeWithPointer
type :: twoPtr
type (two), pointer :: p
end type twoPtr
logical, target :: logv
complex, target :: comv
character, target :: charv
character (len=3), target :: chara
integer, target :: intv
integer, target, dimension (10,2) :: inta
integer, target, allocatable, dimension (:) :: intvla
real, target :: realv
type(two), target :: twov
type(twoPtr) :: arrayOfPtr (3)
type(typeWithPointer), target:: cyclicp1,cyclicp2
logical, pointer :: logp
complex, pointer :: comp
character, pointer :: charp
character (len=3), pointer :: charap
integer, pointer :: intp
integer, pointer, dimension (:,:) :: intap
integer, pointer, dimension (:) :: intvlap
real, pointer :: realp
type(two), pointer :: twop
nullify (logp)
nullify (comp)
nullify (charp)
nullify (charap)
nullify (intp)
nullify (intap)
nullify (intvlap)
nullify (realp)
nullify (twop)
nullify (arrayOfPtr(1)%p)
nullify (arrayOfPtr(2)%p)
nullify (arrayOfPtr(3)%p)
nullify (cyclicp1%p)
nullify (cyclicp2%p)
logp => logv ! Before pointer assignment
comp => comv
charp => charv
charap => chara
intp => intv
intap => inta
intvlap => intvla
realp => realv
twop => twov
arrayOfPtr(2)%p => twov
cyclicp1%i = 1
cyclicp1%p => cyclicp2
cyclicp2%i = 2
cyclicp2%p => cyclicp1
logv = associated(logp) ! Before value assignment
comv = cmplx(1,2)
charv = "a"
chara = "abc"
intv = 10
inta(:,:) = 1
inta(3,1) = 3
allocate (intvla(10))
intvla(:) = 2
intvla(4) = 4
intvlap => intvla
realv = 3.14
allocate (twov%ivla1(3))
allocate (twov%ivla2(2,2))
twov%ivla1(1) = 11
twov%ivla1(2) = 12
twov%ivla1(3) = 13
twov%ivla2(1,1) = 211
twov%ivla2(2,1) = 221
twov%ivla2(1,2) = 212
twov%ivla2(2,2) = 222
intv = intv + 1 ! After value assignment
end program pointers
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