$ yum -y install gcc $ yum -y install gcc-c++ $ yum -y install cgdb $ yum -y install flex $ yum -y install flex-devel $ yum -y install bison
CentOS安装flex（lex）和bison（yacc）环境
原文：https://www.cnblogs.com/Tifahfyf/p/14609274.html
