Insertion Sort in Fortran

Welcome to the Insertion Sort in Fortran page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

program insertionsort
    implicit none
    character(len=256) input1
    character(len=256) output
    character(len=10) :: integer_number
    integer, allocatable :: numbers(:)
    integer :: i
    
    if(command_argument_count() /= 1) call usage()
    call get_command_argument(1, input1)
    if(input1 == "") call usage()
    call convert_to_array(input1, numbers)
    
    if(size(numbers) == 1) call usage()
    
    call insertion_sort(numbers)
    
    output = ""
    do i = 1, size(numbers)
        write(integer_number, '(I0)') numbers(i)
        if(len_trim(output) == 0) then
            output = trim(integer_number)
        else
            output = trim(output) // ", " // trim(integer_number)
        end if
    end do
    print '(A)', trim(output)
    
    
contains
    subroutine usage()
        write(*,'(a)') 'Usage: please provide a list of at least two integers to sort in the format "1, 2, 3, 4, 5"'
        stop
    end subroutine usage
    
    subroutine convert_to_array(input1, numbers)
        implicit none
        character(len=*), intent(in) :: input1
        integer, allocatable, intent(out) :: numbers(:)
        integer :: i, length, pos, io_status
        
        length = 1
        do i = 1, len_trim(input1)
            if (input1(i:i) == ',') length = length + 1
        end do
    
        allocate(numbers(length))
    
        pos = 1
        do i = 1, length
            read(input1(pos:), *, iostat=io_status) numbers(i)
            if (io_status /= 0) call usage()
            pos = index(input1(pos:), ',') + pos
        end do
    end subroutine convert_to_array
    
    subroutine insertion_sort(numbers)
        implicit none
        integer, intent(inout) :: numbers(:)
        integer :: i, j, temp
        
        do i = 2, size(numbers)
            temp = numbers(i)
            j = i - 1
            
            do while (j >= 0 .and. numbers(j) > temp)
                numbers(j+1) = numbers(j)
                j = j - 1
            end do
            numbers(j+1) = temp
        end do
        
    end subroutine insertion_sort
end program insertionsort

Insertion Sort in Fortran was written by:

• leoraggy

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

No 'How to Run the Solution' section available. Please consider contributing.