/usr/ is in libroot-montecarlo-vmc-dev 5.34.14-1build1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/share/
/usr/share/doc/
/usr/share/doc/libroot-montecarlo-vmc-dev/
/usr/share/doc/libroot-montecarlo-vmc-dev/copyright
/usr/include/
/usr/include/root/
/usr/include/root/TMCOptical.h
/usr/include/root/TVirtualMC.h
/usr/include/root/TMCParticleType.h
/usr/include/root/TGeoMCGeometry.h
/usr/include/root/TPDGCode.h
/usr/include/root/TVirtualMCStack.h
/usr/include/root/TMCProcess.h
/usr/include/root/TVirtualMCApplication.h
/usr/include/root/TVirtualMCGeometry.h
/usr/include/root/TMCVerbose.h
/usr/lib/x86_64-linux-gnu/libVMC.so
/usr/share/doc/libroot-montecarlo-vmc-dev/changelog.Debian.gz