#! /bin/bash

# Conversion de décimal en binaire

num="$1"
res=""

if [ "$num" = 0 ]; then
    echo 0
    exit
fi

while [ "$num" -ne 0 ] ; do
    digit="$(expr $num % 2)"
    num="$(expr $num / 2)"
    res="$digit$res"
done

echo $res