(first-follow-select)

代码说明：

  构造LL(1)语法分析程序，任意输入一个文法符号串，并判断它是否为文法的一个句子。程序要求为该文法构造预测分析表，并按照预测分析算法对输入串进行语法分析，判别程序是否符合已知的语法规则，如果不符合（编译出错），则输出错误信息(Construct LL (1) parser, enter an arbitrary string of grammar symbols, and determine if it is a sentence grammar. Procedural requirements for the grammar structure prediction analysis table, and in accordance with predictive analysis algorithms to parse input string, determine whether the program is consistent with the known rules of grammar, if you do not comply (compiler error), the error message is output)