anchor.diff:  
   RUN mkdir -p /opt && curl -L https://github.com/facebook/infer/releases/download/v0.16.0/infer-linux64-v0.16.0.tar.xz | tar -C /opt -x -J
   ENV PATH $PATH:/opt/infer-linux64-v0.16.0/bin/
  +
  +RUN apt-get clean
  
positive.code: 	pdftk-java \
  	poppler-utils \
  	python3-pip \
  	software-properties-common \
  	tzdata \
  	valgrind \
  	vim
  
  RUN curl -L https://apt.llvm.org/llvm-snapshot.gpg.key|apt-key add - \
   && apt-add-repository "deb http://apt.llvm.org/cosmic/ llvm-toolchain-cosmic-8 main" \
  
negative.code: RUN apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 86B72ED9 \
   && echo "deb http://mirror.mxe.cc/repos/apt xenial main" > /etc/apt/sources.list.d/mxeapt.list
  
  RUN apt-get update && apt-get install --no-install-recommends -y \
  	ca-certificates \
  	cloc \
  	colordiff \
  