timestamp=$(shell date +%Y-%m-%d_%H:%M)

all: tp1

tp1: tp1.tex
	@latexmk -pdf tp1.tex
	@if ! cmp --silent build/tp1.pdf tp1_*.pdf; then \
		touch tp1_tmp.pdf; \
		rm tp1*.pdf; \
		cp build/tp1.pdf tp1_${timestamp}.pdf; \
		echo "Updated"; \
	fi

clean:
	@rm -rf build 2>/dev/null