First, I don't know what happed, which means the cause may not as the title suggests.
I was editing with vim. one or two mis-key strokes, now whenever I open file with vim. All the Contents are all selected by default (please see screenshot once the file open up, it is all yellow highlight?, once I select the context "using namespacre std to (line) defines poin, then it look normal again. ). When I select the contents. it look normal again. How can i fix it ? I quit and re-open didn't work. i even empty the vimrc and source the it. didn't work as well. Please help.