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编译原理课程实验报告实验题目：某种简单程序语言的词法分析器的设计与实现专业：计算机科学与技术班级：11060341学 号： 11060341姓名：12 / 12实验目的：设计一个词法分析程序，理解词法分析器实现的原理，掌握程序设计语言中的各类单词的词法分析方法，加深对词法分析原理的理解。实验任务：词法分析是从左向右扫描每行源程序的符号，拼成单词，换成统一的二元式(单词种别，单词符号的属性值)表示。对给定的程序通过词法分析器识别一个个单词符号，并以二元式(单词种别，单词符号的属性值)显示，本程序那么是通过对给定程序段分析后以单词符号和文字提示显示实验流程：程序清单：#include#include#includeusing namespace std;int k=0;struct word char name10; int kind; word1000;char key3510= scanf,short,int,long,float,double,char,struct,union, printf,typedef,const,unsigned,signed,extern,register,static, volatile,void,if,else,switch,case,for,do,while,goto, continue,break,default,sizeof,return,include,bool ;bool cmp(char a) int i; for(int k=0; k35; k+) if(strcmp(a,keyk)=0) return 1; return 0;int main() #ifdef LOCAL freopen(in.txt, r, stdin); freopen(out.txt, w, stdout); #endif int p,q,flag; char a1000,b10,ch; while(gets(a) p=0; int len=strlen(a); while(p=a&ch=A&ch=a&ch=A&ch=0&ch=0&ch=0&ch=0&at=a&at=A&at=0&ch) p+; ch=ap; if(ch=|ch=) b0=; b1=ch; strcpy(wordk.name,b); wordk+.kind=5; ch=a+p; else b0=; strcpy(wordk.name,b); wordk+.kind=5; else if(ch=) p+; ch=ap; if(ch=|ch=) b0=; b1=ch; strcpy(wordk.name,b); wordk+.kind=5; ch=a+p; else b0=; strcpy(wordk.name,b); wordk+.kind=5; else if(ch=!) p+; ch=ap; if(ch=) b0=!; b1=; strcpy(wordk.name,b); wordk+.kind=5; ch=a+p; else b0=!; strcpy(wordk.name,b); wordk+.kind=5; else if(ch=&) p+; ch=ap; if(ch=&) b0=b1=&; strcpy(wordk.name,b); wordk+.kind=5; ch=a+p; else b0=&; strcpy(wordk.name,b); wordk+.kind=5; else if(ch=|) p+; ch=ap; if(ch=|) b0=b1=|; strcpy(wordk.name,b); wordk+.kind=5; ch=a+p; else b0=|; strcpy(wordk.name,b); wordk+.kind=5; for(int i=0; ik; i+) switch(wordi.kind) case 1: printf(标识符,); break; case 2: printf(常量,); break; case 3: printf(关键字,); break; case 4: printf(界符,); break; case 5: printf(运算符,); break; printf(%s)n,wordi.name); int a1=0,a2=0,a3=0,a4=0,a5=0; for(int i=0;ik;i+) if(wordi.kind=1) a1+; else if(wordi.kind=2) a2+; else if(wordi.kind=3) a3+; else if(wordi.kind=4) a4+; else if(wordi.kind=5) a5+; printf(标识符：%dn常量：%dn关键字：%dn界符：%dn运算符：%dn,a1,a2,a3,a4,a5); return 0;运行结果：
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