Count number of lines under each header in a text file using bash shell script -

i can in python or other high level language. interested in doing bash.

here file format:

head-xyz item1 item2 item3 head-abc item8 item5 item6 item9 

what print following output:

head-xyz: 3 head-abc: 4 

header have specific pattern similar example gave above. items have specific patterns in example above. interested in count of items under each header.

you can use awk:

awk '/head/{h=$0}{c[h]++}end{for(i in c)print i, c[i]-1}' input.file