Hello, I am trying to install R. Thank you in advance for any help! Yue li@li-HP-Pavilion-Desktop-590-p0xxx:~/R-3.6.0$ ./configure checking build system type... x86_64-pc-linux-gnu checking host system type... x86_64-pc-linux-gnu loading site script './config.site' loading build-specific script './config.site' checking for pwd... /bin/pwd checking whether builddir is srcdir... yes checking whether ln -s works... yes checking for ar... ar checking for a BSD-compatible install... /usr/bin/install -c checking for sed... /bin/sed checking for which... /usr/bin/which checking for less... /usr/bin/less checking for gtar... no checking for gnutar... no checking for tar... /bin/tar checking for tex... no checking for pdftex... no configure: WARNING: you cannot build PDF versions of the R manuals checking for pdflatex... no configure: WARNING: you cannot build PDF versions of vignettes and help pages checking for makeindex... no checking for texi2any... no configure: WARNING: you cannot build info or HTML versions of the R manuals checking for texi2dvi... no checking for kpsewhich... no checking for latex inconsolata package... checking for unzip... /usr/bin/unzip checking for zip... /usr/bin/zip checking for gzip... /bin/gzip checking for bzip2... /bin/bzip2 checking for firefox... /usr/bin/firefox using default browser ... /usr/bin/firefox checking for acroread... no checking for acroread4... no checking for xdg-open... /usr/bin/xdg-open checking for working aclocal... missing checking for working autoconf... missing checking for working autoheader... missing checking for bison... no checking for byacc... no checking for yacc... no checking for notangle... false checking for realpath... /usr/bin/realpath checking for pkg-config... no checking for gcc... gcc checking whether the C compiler works... yes checking for C compiler default output file name... a.out checking for suffix of executables... checking whether we are cross compiling... no checking for suffix of object files... o checking whether we are using the GNU C compiler... yes checking whether gcc accepts -g... yes checking for gcc option to accept ISO C89... none needed checking how to run the C preprocessor... gcc -E checking for grep that handles long lines and -e... /bin/grep checking for egrep... /bin/grep -E checking whether gcc needs -traditional... no checking for ANSI C header files... yes checking for sys/types.h... yes checking for sys/stat.h... yes checking for stdlib.h... yes checking for string.h... yes checking for memory.h... yes checking for strings.h... yes checking for inttypes.h... yes checking for stdint.h... yes checking for unistd.h... yes checking minix/config.h usability... no checking minix/config.h presence... no checking for minix/config.h... no checking whether it is safe to define __EXTENSIONS__... yes checking how to run the C preprocessor... gcc -E looking for a modern Fortran compiler checking for gfortran... no checking for g95... no checking for xlf95... no checking for f95... no checking for fort... no checking for ifort... no checking for ifc... no checking for efc... no checking for pgfortran... no checking for pgf95... no checking for lf95... no checking for ftn... no checking for nagfor... no checking for xlf90... no checking for f90... no checking for pgf90... no checking for pghpf... no checking for epcf90... no checking for g77... no checking for xlf... no checking for f77... no checking for frt... no checking for pgf77... no checking for cf77... no checking for fort77... no checking for fl32... no checking for af77... no checking whether we are using the GNU Fortran compiler... no checking whether accepts -g... no configure: error: No Fortran compiler found