#!/bin/bash

function rec {
  local x=$1
  if test $1 -lt 5
  then
    ((x++))
    echo "rec $x"
    rec $x
  else
    echo $x
  fi
}

function makedirs {
    mkdir -p 1/2/5 1/2/6 1/3 1/4/7 1/4/8
}

function getsubdirs {
    subdirs=()
    currentdir="$1"
    for i in "$currentdir"/*;do
        if test -d "$i"; then
            #~ echo addsub "$i" 1>&2
            subdirs+=("$i")
        fi
    done
}

function printcontent {
    for i in "$1"/*; do
        echo $i
        #~ echo "`du -h "$i"|cut -f1`" "$i"
    done
}

function dfspreorder {
    local currentdir="$1"
    echo preorder "$1"
    getsubdirs "$currentdir"
    for subdir in "${subdirs[@]}"; do
        dfspreorder "$subdir"
        #~ echo inorder "$currentdir"
    done
    #~ echo postorder "$currentdir"
}

function dfsinorder {
    local currentdir="$1"
    getsubdirs "$currentdir"
    for subdir in "${subdirs[@]}"; do
        dfsinorder "$subdir"
        echo inorder for "$currentdir"
    done
    echo inorder afterfor "$currentdir"
}

function dfspostorder {
    local currentdir="$1"
    getsubdirs "$currentdir"
    for subdir in "${subdirs[@]}"; do
        dfspostorder "$subdir"
    done
    echo postorder "$currentdir"
}

count=0
subdirs=()
#rec 0
#recdir `pwd`
rm -rf 1
makedirs
root=`realpath 1`

dfspreorder "$root" #ok
dfspostorder "$root" #ok
dfsinorder "$root" #ok