$ du -ah * | sort -nr
 12K    te
4.0K    te/a4.txt
4.0K    a4.txt
2.0K    te/a3.txt
2.0K    te/a2.txt
2.0K    te/a1.txt
2.0K    a3.txt
2.0K    a2.txt
2.0K    a1.txt



The hierarchy is:
~/te/a1.txt
~/te/a2.txt
~/te/a3.txt
~/te/a4.txt
~/a1.txt
~/a2.txt
~/a3.txt
~/a4.txt


and the output should be:

4.0K    te/a4.txt
4.0K    a4.txt
2.0K    te/a3.txt
2.0K    te/a2.txt
2.0K    te/a1.txt
2.0K    a3.txt
2.0K    a2.txt
2.0K    a1.txt