    tail -1 |
    sed 's/ /\n/g' |
    while read a; do
        bc <<< "obase=2; print $a" | sed 's/^.*1\(0*\)$/\1/' | wc -c
    done |
    awk '
    BEGIN { ans = 100000 }
    { ans = ans < $1 ? ans : $1 }
    END {print ans}'  # take minimum