#include
using namespace std;
const int max_word = 505;
//关键字
const char keyWord[13][20] = {"main","if","else","do","while","for","switch",
"case","int","double","float","long","void"};
//单词表
struct Word{
char value[20];//单词值
int type;//单词种类
int line;//行号
}w[max_word];
//四元式
struct si_Yuan{
string op;//运算符
string s1;
string s2;
string res;//结果
}sy[105];
//文件流
FILE *fin,*fout;
int line = 1;
char token[12];//存放单词
int flag = 0;//判断是否获取字符
int flag1 = 0,flag2;//flag1判断是否项已经产生miss错误;
int e = 0;//错误个数
int sy_num = 0;//四元式的个数
string op,s1,ss1,s2,res,res1,res2,op2,op1;
int op_num = 0,op_num1 = 0;//运算符的个数
int sy_id;//四元式的序号
string var[300];//已经声明的变量
int var_num = 0;//声明变量的个数
int sent_id;//判断if,while语句
string equ[300];//=
int a,b,c;
int equ_num = 1; //=个数
int cnt = 0,token_num = 0;//当前字符
int row = 1;//当前行数
char ch;
char ch1;
int word_num = 0;//单词的总个数
int word_cnt = 0;
string temp;
char str_int[20];
stackword_stack;//保存
stackop_stack;
//程序
void S();
void P();//(){分程序}
void P1();//分程序
void A();//变量说明部分
void B();//语句部分
void B1();
int C();//变量说明
void D();//标识符表
void D1();
void E();//标识符
void F();//字母
void G();//数字
void H();//语句
void I();//赋值语句
void J();//条件语句
void K();//循环语句
int L();//关系运算符
void M();//表达式
void M1();
void N();//项
void N1();
int O();//加法运算符
int Q();//乘法运算符
void R();//常量
void S();//无符号整数
void T();//数字序列
void W();//复合语句
void X();//条件
void Y();//语句1
void Z();//因子
//构造四元式
void siYuan(string op,string s1,string s2,string res)
{
sy[sy_num].op =op;
sy[sy_num].s1=s1;
sy[sy_num].s2=s2;
sy[sy_num].res=res;
sy_num++;
}
void printFour()//输出四元式
{
ofstream out("sy.txt");
int i;
for(i=0;ivar_num)
{
cout<<"第 "<='a' && ch <= 'z') || (ch >= 'A' &&ch <= 'Z')){
//可能为标识符或者变量名
while((ch>='a' && ch <= 'z') || (ch >= 'A' &&ch <= 'Z') || (ch >= '0' && ch <= '9')){
token[token_num++] = ch;
ch = getc(fin);
}
token[token_num++] = '\0';
for(int i = 0;i <13;i++){
if(strcmp(token,keyWord[i]) == 0){
//3为关键词
return 3;
}
}
//2为标识符
return 2;
}
//是数字
else if(ch >= '0' && ch <= '9'){
while((ch >= '0'&& ch <= '9') || ch == '.'){
token[token_num++] = ch;
ch = getc(fin);
}
return 1;
}
else{
token[token_num++] = ch;
switch(ch){
case '(': ch = getc(fin); return 16;
case ')': ch = getc(fin); return 17;
case '{': ch = getc(fin); return 33;
case '}': ch = getc(fin); return 34;
case '+':
ch = getc(fin);
if(ch == '+'){
token[token_num++] = ch;
ch = getc(fin);
return 29;
}
else{
return 18;
}
case '-':
ch = getc(fin);
if(ch == '-'){
token[token_num++] = ch;
ch = getc(fin);
return 30;
}
else{
return 19;
}
case '*':
ch = getc(fin);
if(ch == '/'){
token[token_num++] = ch;
ch = getc(fin);
return 32;
}
else{
return 20;
}
case '/':
ch = getc(fin);
if(ch == '*'){
token[token_num++] = ch;
ch = getc(fin);
return 31;
}
else{
return 21;
}
//这里要重新编码
case '=':
ch = getc(fin);
if(ch == '='){
token[token_num++] = ch;
ch = getc(fin);
return 23;
}
else{
return 22;
}
case '>':
ch = getc(fin);
if(ch == '='){
token[token_num++] = ch;
ch = getc(fin);
return 24;
}
else{
return 23;
}
case '<':
ch = getc(fin);
if(ch == '='){
token[token_num++] = ch;
ch = getc(fin);
return 26;
}
else{
return 25;
}
case ';': ch = getc(fin); return 27;
case '"': ch = getc(fin); return 28;
case '!':
ch = getc(fin);
if(ch == '='){
token[token_num++] = ch;
ch = getc(fin);
return 37;
}
else{
return 36;
}
case '#': ch = getc(fin); return -2;
case ',': ch = getc(fin); return 35;
case EOF: return -1;
default: ch = getc(fin); return -10;
}
}
}
void getWord(){
int temp;
while(1){
temp = judge_token();
if(temp==-1){
break;
}
switch(temp){
case -10:
//cout<<"第 "<"<>res;
siYuan(op,s1,s2,res);
//修改while跳转的序号
stringstream sss2;
sss2<>sy[sent_id].res;
}
else{
error("extra fuhao");
}
}
//赋值语句
void I(){
if(strcmp(w[word_cnt].value,"=") == 0){
word_cnt++;
//word_stack.push(w[word_cnt].value);
M();
if(e > 0){
return;
}
if(op_stack.size() > 0){
op = op_stack.top();
op_stack.pop();
s2 = word_stack.top();
word_stack.pop();
s1 = word_stack.top();
word_stack.pop();
res = word_stack.top();
word_stack.pop();
siYuan(op,s1,s2,res);
}
else{
s1 = word_stack.top();
word_stack.pop();
res = word_stack.top();
word_stack.pop();
siYuan("=",s1,"",res);
}
}
else{
error("miss = ");
word_cnt--;
}
}
//if语句
void J(){
cout<<"J()"< 0 && e == 0){
op = op_stack.top();
op_stack.pop();
s2 = word_stack.top();
word_stack.pop();
s1 = word_stack.top();
word_stack.pop();
siYuan(op,s1,s2,res);
}
if(strcmp(w[word_cnt].value,")")){
error("miss )");
word_cnt--;
}
word_cnt++;
//四元式置为空
op = "";
s1 = "";
s2 = "";
res = "";
Y();//语句1
stringstream ss;
ss<>sy[sent_id].res;
sent_id = sy_num;
op = "go";
s1 = "";
s2 = "";
res = "";
siYuan(op,s1,s2,res);
if(strcmp(w[word_cnt].value,"else")){
error("miss else");
word_cnt--;
}
word_cnt++;
Y();
stringstream ss2;
ss2<>sy[sent_id].res;
}
//while语句
void K(){
cout<<"K()"<0 && e == 0){
op = op_stack.top();
op_stack.pop();
s2 = word_stack.top();
word_stack.pop();
s1 = word_stack.top();
word_stack.pop();
siYuan(op,s1,s2,res);
}
//cout< 0 && e == 0){
op = op_stack.top();
op_stack.pop();
s2 = word_stack.top();
word_stack.pop();
s1 = word_stack.top();
word_stack.pop();
stringstream ss;
ss << op_num;
res = "t"+ss.str();
word_stack.push(res);
siYuan(op,s1,s2,res);
}
if(strcmp(w[word_cnt].value,">") == 0){
op = "<=";
}
else if(strcmp(w[word_cnt].value,">=") == 0){
op = "<";
}
else if(strcmp(w[word_cnt].value,"<") == 0){
op = ">=";
}
else if(strcmp(w[word_cnt].value,"<=") == 0){
op = ">";
}
else if(strcmp(w[word_cnt].value,"==") == 0){
op = "!=";
}
else if(strcmp(w[word_cnt].value,"!=") == 0){
op = "==";
}
//cout< 1 && e == 0){
op = op_stack.top();
op_stack.pop();
s2 = word_stack.top();
word_stack.pop();
s1 = word_stack.top();
word_stack.pop();
stringstream ss;
ss << op_num;
res = "t"+ss.str();
word_stack.push(res);
siYuan(op,s1,s2,res);
}
}
}
//项 ,消除左递归
void N(){
cout<<"N()"< 1 && e == 0){
op = op_stack.top();
op_stack.pop();
s2 = word_stack.top();
word_stack.pop();
s1 = word_stack.top();
word_stack.pop();
stringstream ss;
ss << op_num;
res = "t"+ss.str();
word_stack.push(res);
siYuan(op,s1,s2,res);
}
}
}
//因子
void Z(){
//cout< 22 && w[word_cnt].type <= 26) || w[word_cnt].type == 37)){
return 1;
}
return 0;
}
//加法运算符
int O(){
if(w[word_cnt].type == 18 || w[word_cnt].type == 19){
return 1;
}
return 0;
}
//乘法运算符
int Q(){
if(w[word_cnt].type == 20 || w[word_cnt].type == 21){
return 1;
}
return 0;
}
int main(){
fin = fopen("compiler.txt","r");
getWord();
S();
if(e==0)
{
printFour();
}
else
{
cout<<"\nSorry,can not generate siYuan."<
