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1、编译原理实验报告实验编号实验二实验名称词法分析程序的设计与实现学号：姓名：提交日期：成绩：一．实验二：词法分析程序的设计与实现【实验目的和要求】设计、编制、调试一个具体的词法分析程序，加深对词法分析原理的理解。【实验描述】通过对PL/0词法分析程序（GETSYM）的分析，并在此基础上按照附录A中给出的PL/0语言的语法描述，编写一个PL/0语言的词法分析程序。此程序应具有如下功能：输入为字符串（待进行词法分析的源程序），输出为单词串，即由（单词、类别）所组成的二元组序列。有一定检查错误的能力，例如发现2A这类不能作为单词的字符串。【主要变量名说明】char*key[8
2、]={"if","else","for","while","do","return","break","continue"};确定关键字char*border[6]={",",";","{","}","(",")"};确定界符char*arithmetic[4]={"+","-","*","/"};确定算术运算符char*relation[6]={"<","<=","=",">",">=","<>"};确定关系运算符【程序清单】#include#include#include#include#
3、defineNULL0#includeusingnamespacestd;FILE*fp;charcbuffer;char*key[8]={"if","else","for","while","do","return","break","continue"};char*border[6]={",",";","{","}","(",")"};char*arithmetic[4]={"+","-","*","/"};char*relation[6]={"<","<=","=",">",">=","<>"};char*consts[20];char*la
4、bel[20];intconstnum=0,labelnum=0;/////////////////////////////////////////////////////////////////////////////////////////////////////intsearch(charsearchchar[],intwordtype){inti=0;switch(wordtype){case1:{for(i=0;i<=7;i++){if(strcmp(key[i],searchchar)==0)return(i+1);}return0;}case2:{for
5、(i=0;i<=5;i++){if(strcmp(border[i],searchchar)==0)return(i+1);}return(0);}case3:{for(i=0;i<=3;i++){if(strcmp(arithmetic[i],searchchar)==0){return(i+1);}}return(0);}case4:{for(i=0;i<=5;i++){if(strcmp(relation[i],searchchar)==0){return(i+1);}}return(0);}case5:{for(i=0;i<=constnum;i++){if(
6、i!=constnum){if(strcmp(consts[i],searchchar)==0)return(i+1);}}consts[i-1]=(char*)malloc(sizeof(searchchar));strcpy(consts[i-1],searchchar);constnum++;return(i);}case6：{for(i=0;i<=labelnum;i++){if(i!=labelnum){if(strcmp(label[i],searchchar)==0)return(i+1);}}label[i-1]=(char*)malloc(sizeo
7、f(searchchar));strcpy(label[i-1],searchchar);labelnum++;return(i);}default:return0;}}/////////////////////////////////////////////////////////////////////////////////////////////////////charalphaprocess(charbuffer){intatype;inti=-1;charalphatp[20];while((isalpha(buffer))
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9、(isdi
