List directory size, bash script

				
					#!/usr/bin/env bash
# it searches in the current working directory

function calculate_size
# takes a path as input
{
    du  -mc "$1"  | tail -1 | awk '{print $1}'
}

function list_dirs
{
    # find . -depth 1 -type d | while read -r line; do
    find . -maxdepth 1 -type d | while read -r line; do
        printf "$my_format" "$(calculate_size "$line")" "mb" "$line" 
    done
}


function make_divider
{
    nr=$(tput cols)
    for i in `seq 1 $nr`; do printf "-";done
}

function my_main
{
    my_format="%9s\t%2s\t %s\n"

    nr=$(tput cols)
    my_divider=$(make_divider)
 
    clear
    echo
    echo "$my_divider"
    echo 
    echo "Dirs: "$(pwd)
    printf "\n"
    echo "$my_divider"

    list_dirs | sort -r -nk1 2>/dev/null
       
   echo "$my_divider"
   printf "\n\n"
 }

# ===========================================================
# Now follows the actual program
my_main