I wrote this calculator when I volunteered to work out the expenses for our 1981 ski trip to Jackson Hole. I wasn't even sure how to approach the calculation so I just started writing facts into a file. Pretty soon I realized that if I could just sum the groups and then bring those sums into other groups then I'd pretty much have it. I wrote a small AWK script to do just that and print a report. I finished the script and the report together. -- WardCunningham (copy&pasted from http://c2.com/doc/expense/)

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Oh my goodness! Truly inspirational program (or should I say a poem)! (See also WriteSmallButUsefulProgramsEveryDay for more examples of this beautiful style.) -- JuneKim