这是一个实现词法分析的小程序

				一、语言规定
				程序实现一个语言的词法分析，其中此语言的定义
				
				关键字(类别1)：
				"double","int","struct","break","else","long","switch","case","enum","register","typedef","char","return","const","float","short","continue","for","signed","void","default","goto","do","if","while","static","then"
				
				标识符(类别2):标识符后必须跟空格、')'、'='、','、';'、'>'、'				
				常数(类别3)
				
				
				运算符(类别4):  + - * / > < =
				
				界符(类别5)：；，(  )
				
				
				二、程序说明：
				程序文件Lex.java
				程序中的输入文件：file.txt（注意路径正确）
				程序中的输出文件：result.txt（二元式）
				输入'#'代表程序结束。