A GCC is not installed error
But you can see the GCC GCC - v version is 4.8 shows the GCC has been installed
This time can yum remove GCC and reinstall
After reinstalling or an error might be install GCC incomplete you can view the g + + have installed
Do not check if the g + + -v you can reinstall the g + +
Yum install g + + if you have already installed will never find a g + + -v
Can try to yum install GCC - install the g + c + +