Bdtyktl

Originally gcc -o main main.cpp produce same error like

main.cpp:10:20: fatal error: iostream: No such file or directory

#include <iostream>

But after install gcc with brew (brew install gcc)
and link (brew link gcc), the version of gcc is renew (4.8.1 -> 8.2.0)

So compiling with gcc(gcc -o main main.cpp) is okay but
g++ -o main main.cpp still produce same error message.

What should I do for g++ compile?

gcc -v says

Using built-in specs.

COLLECT_GCC=gcc

COLLECT_LTO_WRAPPER=/usr/local/Cellar/gcc/8.2.0/libexec/gcc/x86_64- 

apple-darwin18.0.0/8.2.0/lto-wrapper

Target: x86_64-apple-darwin18.0.0

Configured with: ../configure --build=x86_64-apple-darwin18.0.0 -- 

prefix=/usr/local/Cellar/gcc/8.2.0 -- 

libdir=/usr/local/Cellar/gcc/8.2.0/lib/gcc/8 --enable- 

languages=c,c++,objc,obj-c++,fortran --program-suffix=-8 --with- 

gmp=/usr/local/opt/gmp --with-mpfr=/usr/local/opt/mpfr --with- 

mpc=/usr/local/opt/libmpc --with-isl=/usr/local/opt/isl --with-system- 

zlib --enable-checking=release --with-pkgversion='Homebrew GCC 8.2.0' - 

-with-bugurl=https://github.com/Homebrew/homebrew-core/issues -- 

disable-nls --disable-multilib --with-native-system-header- 

dir=/usr/include --with- 

sysroot=/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk

Thread model: posix

gcc version 8.2.0 (Homebrew GCC 8.2.0)

But g++ -v says

g++: warning: couldn’t understand kern.osversion ‘18.2.0

Using built-in specs.

COLLECT_GCC=g++

COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/x86_64-apple- 

darwin12.5.0/4.8.1/lto-wrapper

Target: x86_64-apple-darwin12.5.0

Configured with: ../gcc-4.8.1/configure --enable-languages=c++,fortran

Thread model: posix

gcc version 4.8.1 (GCC)