编译原理
#include<stdio.h>#include<stdlib.h>
#include"cifa.h"
#define MAX 20
char index_char[10]={'+','-','*','/','(',')','=','#','S','E'};
int get_index_char(char i)
{
int j;
for(j=0;j<10;j++)
{
if(index_char[j] == i)
return j;
}
return -1;
}
//规约规则
struct rule{
char x;
int y;
}r[8]={{' ',0},{'S',3},{'E',3},{'E',3},{'E',2},{'E',3},{'E',1},{'E',3}};
/*0-16 表示状态节点，21-27 表示规约标号，-1 表示出错，20 表示成功*/
int table[17][11]={
{2,-1,3,-1,-1,4,-1,-1,-1,13,1},{-1,5,-1,6,14,-1,-1,7,-1,-1,-1},
{26,26,26,26,26,26,26,26,26,-1,-1},{2,-1,3,-1,-1,4,-1,-1,-1,-1,8},
{2,-1,3,-1,-1,4,-1,-1,-1,-1,11},{2,-1,3,-1,-1,4,-1,-1,-1,-1,9},
{2,-1,3,-1,-1,4,-1,-1,-1,-1,10},{2,-1,3,-1,-1,4,-1,-1,-1,-1,16},
{24,5,24,6,16,24,24,24,24,-1,-1},{22,5,22,6,16,22,22,22,22,-1,-1},
{23,5,23,6,16,23,23,23,23,-1,-1},{-1,5,-1,6,16,-1,12,-1,-1,-1,-1},
{25,25,25,25,25,25,25,25,25,-1,-1},{-1,-1,-1,-1,-1,-1,-1,-1,20,-1,-1},
{2,-1,3,-1,-1,4,-1,-1,-1,-1,15},{27,5,27,6,16,27,27,27,27,-1,-1},
{21,5,21,6,16,21,21,21,21,-1,-1}};
struct status{
int stack[MAX];
int top;
};
//初始化栈
void init_stack1(struct status *p)
{
if(!p)
printf("\n初始化状态栈出错!\n");
p->top = -1;
}
//压栈
void push1(struct status *p,int x)
{
if(p->top < MAX-1)
{
p->top++;
p->stack[p->top] = x;
}
else printf("\n状态栈溢出!\n");
}
//弹栈
int pop1(struct status *p)
{
int x;
if(p->top != 0)
{
x = p->stack[p->top];
p->top--;
return x;
}
else
{
printf("\n状态栈1空!\n");
return 0;
}
}
//取栈顶元素
int get_top1(struct status *p)
{
int x;
if(p->top != -1)
{
x = p->stack[p->top];
return x;
}
else
{
printf("\n状态栈2空!\n");
return 0;
}
}
//遍历栈元素
void out_stack1(struct status *p)
{
int i;
if(p->top <0)
printf("\n状态栈3空!\n");
for(i=0; i<=p->top;i++)
{
printf("%d",p->stack[i]);
}
}
struct symbol_instr{
char stack[MAX];
int top;
};
//初始化栈
void init_stack2(struct symbol_instr *p)
{
if( !p)
printf("\n初始化符号栈出错!\n");
p->top = -1;
}
//压栈
void push2(struct symbol_instr *p,char x)
{
if(p->top < MAX-1)
{
p->top++;
p->stack[p->top] = x;
}
else printf("\n符号栈溢出!\n");
}
//弹栈
char pop2(struct symbol_instr *p)
{
char x;
if(p->top != -1)
{
x = p->stack[p->top];
p->top--;
return x;
}
else
{
printf("\n符号栈1空!\n");
return 0;
}
}
//取栈顶元素
char get_top2(struct symbol_instr *p)
{
char x;
if(p->top != -1)
{
x = p->stack[p->top];
return x;
}
else
{
printf("\n符号栈2空!\n");
return 0;
}
}
//自栈底到栈顶遍历栈元素
void out_stack21(struct symbol_instr *p)
{
int i;
if(p->top <0)
printf("\n符号栈3空!\n");
for(i=0; i<=p->top;i++)
{
printf("%c",p->stack[i]);
}
}
//自栈顶到栈底遍历栈元素
void out_stack22(struct symbol_instr *p)
{
int i;
if(p->top <0)
printf("\n符号栈4空!\n");
for( i=p->top;i>=0;i--)
{
printf("%c",p->stack[i]);
}
}
int lookup(int a)
{
switch(a)
{
case 2:
return 2;
case 3:
return 3;
case 4:
return 4;
case 5:
return 5;
case 6:
return 6;
case 7:
return 7;
case 12:
return 12;
case 14:
return 14;
case 16:
return 16;
}
}
//移进
void shift(int a,char ch,struct status *status_p,struct symbol_instr *symbol_p)
{
push1(status_p,a);
push2(symbol_p,ch);
}
int go(int i,int n)
{
return table[i][n];
}
//规约
void statute(int j,struct status *status_p,struct symbol_instr *symbol_p)
{
int i,k,n,m;
char ch;
k=r[j].x;
while(k--)
{
pop1(status_p);
pop2(symbol_p);
}
push2(symbol_p,r[j].y);
i=get_top1(status_p);
ch=get_top2(symbol_p);
n=get_index_char(ch);
m=go(i,n);
push1(status_p,m);
}
void main()
{
FILE *fp,*out;
char name[20];
char ch;
int i,j,index;
printf(" *********************************** \n");
printf(" 词法分析器 \n");
printf(" *********************************** \n");
printf("Please input the name of source:");
scanf("%s",name);
fp=fopen(name,"r");
out=fopen("result.txt","w");
analysis();
fclose(fp);
fclose(out);
printf(" *********************************** \n");
printf(" 语法分析器 \n");
printf(" *********************************** \n");
fp=fopen("result.txt","r");
struct status * status_p;
struct symbol_instr * symbol_p;
status_p=(struct status *)malloc(sizeof(status)); //状态栈
symbol_p=(struct symbol_instr *)malloc(sizeof(symbol_instr)); //符号栈（字符类型）
init_stack1(status_p);
init_stack2(symbol_p);
//压进栈初始元素
push1(status_p,0);
push2(symbol_p,'#');
while(!feof(fp))
{
ch=getc(fp);
if(ch=='+')
{
i=get_top1(status_p);
j=lookup(table[i][1]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",'+');
statute(j,status_p,symbol_p);
}
}
else if(ch=='-')
{
i=get_top1(status_p);
j=lookup(table[i][2]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",'-');
statute(j,status_p,symbol_p);
}
}
else if(ch=='*')
{
i=get_top1(status_p);
j=lookup(table[i][3]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",'*');
statute(j,status_p,symbol_p);
}
}
else if(ch=='/')
{
i=get_top1(status_p);
j=lookup(table[i][4]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",'/');
statute(j,status_p,symbol_p);
}
}
else if(ch=='(')
{
i=get_top1(status_p);
j=lookup(table[i][5]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",'(');
statute(j,status_p,symbol_p);
}
}
else if(ch==')')
{
i=get_top1(status_p);
j=lookup(table[i][6]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",')');
statute(j,status_p,symbol_p);
}
}
else if(ch=='=')
{
i=get_top1(status_p);
j=lookup(table[i][7]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",'=');
statute(j,status_p,symbol_p);
}
}
else if(ch=='#')
{
i=get_top1(status_p);
j=lookup(table[i][8]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
statute(j,status_p,symbol_p);
}
else if(j==20)
printf("分析成功！");
}
else
{
i=get_top1(status_p);
j=lookup(table[i][0]);
if(j<=16)
shift(j,ch,status_p,symbol_p);
else if(20<j&&j<28)
{
printf("%c\n",ch);
statute(j,status_p,symbol_p);}
}
}
fclose(fp);
}
这是编译原理的赋值语句的翻译程序，不知道是哪里有问题，求高手指点……
