AOC2019day1part2

1-2.sh

#!/bin/sh

set -eu

total=0

while read -r val; do
        xtra=$((val / 3 - 2))
        while [ "$xtra" -gt 0 ]; do
                total=$((total + xtra))
                xtra=$((xtra / 3 - 2))
        done
done

echo $total