OUTPUT = build
TEX = latexmk --output-directory=$(OUTPUT)/
SOURCES := $(shell find -name '*.tex' | sort)
PDFS := $(shell find -name '*.tex' | sed 's/.tex$$/.pdf/' | sort)

%.pdf: %.tex
	$(TEX) $<

cheese:
	$(TEX) -recorder -pdf $(SOURCES)
	cp build/*.pdf .
	pdfjoin -o worksheets.pdf $(PDFS)

clean:
	rm *.pdf
	rm -r $(OUTPUT)/