#include<stdio.h>
#include<string.h>
#include<math.h>
#include <stdlib.h>
char prog[80],token[8];
char ch;
int syn,p,m,n,sum;
int count,zhengfu;//1=-,2=+,0=wu
int xiaoshu,zhishu,zhishumi,fuhao;
int temp2;
double temp,shixiaoshu;
int repeat;
char*rwtab[6]={"function","if","then","while","do","endfunc"};
FILE *fp;
void printToFile()
{
if ((fp = fopen("E:\\jieguo.txt","a")) == NULL)
{
printf("檔案保存失敗!\n");
exit(0);
}
do
{
scaner();
switch(syn)
{
case 11:
fputc('(',fp);
fprintf(fp,"%d,%s",syn,token);
fputc(')',fp);
fputc('\n',fp);
break;
case -1:
fprintf(fp,"%s","error");
break;
////////////////處理空白字符
case 100:
break;
//////////////////////*
default:
fputc('(',fp);
fprintf(fp,"%d,%s",syn,token);
fputc(')',fp);
fputc('\n',fp);
}
}while(syn != 0);
}
void redToFile()
{
if ((fp = fopen("E:\\yuanma.txt","r")) == NULL)
{
printf("檔案讀取失敗!\n");
exit(0);
}
while ((ch = fgetc(fp)) != EOF)
{
prog[++p] = ch;
printf("%c",ch);////////////將檔案輸出到螢屏上.
}
fclose(fp);
}
void main(){
int choose1,choose2;
p=0;
count=0;
shixiaoshu=0;
zhishu=0;
repeat=0;
printf("輸入1表示從檔案讀入字串(yuanma.txt)\n");
printf("輸入2表示從鍵盤輸入字串\n");
printf("請輸入您的選擇:\n");
scanf("%d",&choose1);
printf("輸入1表示將結果存入檔案(jieguo.txt)\n");
printf("輸入2表示將結果顯示到螢屏上\n");
printf("請輸入您的選擇:\n");
scanf("%d",&choose2);
if (choose1==2)//////////從鍵盤輸入
{
p = 0;
printf("please input string:\n");
do
{
scanf("%c",&ch);
prog[++p] = ch;
}while(ch != '#');
}
else///////////////從檔案讀入
{
redToFile();
}
p = 0;
if (choose2 == 2)
{
if ((fp = fopen("E:\\yuanma.txt","r")) == NULL)
{
printf("檔案讀取失敗!\n");
exit(0);
}
do{
scanf("%c",&ch);
prog[p++]=ch;
}
while(ch!='#');
p=0;
do{
scaner();
switch(syn)
{
case 11:
if(xiaoshu==0){
printf("\n(%d,%d)",syn,sum);break;
}
else if(zhishu==1){
printf("\n(%d,%10.5e)\n",syn,sum);
zhishu=0;xiaoshu=0;
break;
}
else if(xiaoshu==1){
printf("(%d,%8.4f)\n",syn,sum);
xiaoshu=0;
break;
}
case -1:printf("\n erron");
break;
default:printf("\n(%d,%s)",syn,token);
}
}while(syn!=0);
else
{printToFile();}
}
}
void scaner()
{
sum=0;
shixiaoshu=0;
for(n=0;n<8;n++)
token[n]=NULL;
ch=prog[p++];
while(ch==' '||ch=='\n')
ch=prog[p++];
if((ch>='a'&&ch<='z')||(ch>='A'&&ch<='Z'))
{ m=0;
while((ch>='a'&&ch<='z')||(ch>='0'&&ch<='9')||(ch>='A'&&ch<='Z'))
{
token[m++]=ch;
ch=prog[p++];
}
token[m]='\0';
ch=prog[p--];
syn=10;
for(n=0;n<6;n++)
if(strcmp(token,rwtab[n])==0)
{
syn=n+1;
break;
}
}
else
if(ch>='0'&&ch<='9')
{
IsNum:
if(zhengfu==1){
token[m++]='-';
}///////////
while(ch>='0'&&ch<='9')
{
sum=sum*10+ch-'0';
ch=prog[p++];
}
if(ch=='.'){
xiaoshu=1;
ch=prog[p++];
count=0;
while(ch>='0'&&ch<='9'){
temp=(ch-'0')*pow(0.1,++count);
shixiaoshu=shixiaoshu+temp;
ch=prog[p++];
}
sum=sum+shixiaoshu;
}
if(ch=='e'||ch=='E'){
zhishu=1;
ch=prog[p++];
if(ch=='-'){
fuhao=1;
ch=prog[p++];
}
while(ch>='0'&&ch<='9')
{
zhishu=zhishu*10+ch-'0';
ch=prog[p++];
}
if(fuhao)
sum=sum*pow(0.1,fuhao);
else
sum=sum*pow(10,fuhao);
}
if(zhengfu==1)
{
sum=-sum;
zhengfu=0;
}
ch=prog[p--];
syn=11;
}
else
switch(ch)
{
case'<':m=0;token[m++]=ch;
ch=prog[p++];
if(ch=='>')
{
syn=21;
token[m++]=ch;
}
if(ch=='=')
{
syn=22;
token[m+1]=ch;
}
else
{
syn=20;
ch=prog[p--];
}
break;
case'>':m=0;token[m++]=ch;
ch=prog[p++];
if(ch=='=')
{
syn=24;
token[m++]=ch;
}
else
{
syn=23;
ch=prog[p++];
}
break;
case'=':m=0;token[m++]=ch;
ch=prog[p++];
if(ch=='=')
{
syn=25;
token[m++]=ch;
}
else
{
syn=18;
ch= prog[p--];
}
break;
case'!':m=0;token[m++]=ch;
ch=prog[p++];
if(ch=='=')
{
syn=22;
token[m++]=ch;
}
else
syn=-1;
break;
case'+':temp2=prog[p];
token[m++]=ch;
if(temp2>='0'&&temp2<='9'&&repeat==1)
{
zhengfu=2;
ch=prog[p++];
repeat=0;
goto IsNum;
}
if((temp2=='+'||temp2=='-')&&repeat==0)
{
repeat=1;
ch=prog[p++];
}
syn=13;
break;
case'-':temp2=prog[p];
token[m++]=ch;
if(temp2>='0'&&temp2<='9'&&repeat==1)
{
zhengfu=1;
ch=prog[p++];
repeat=0;
goto IsNum;
}
if((temp2=='+'||temp2=='-')&&repeat==0)
{
repeat=1;
ch=prog[p++];
}
syn=14;
break;
case'*':
temp2=prog[p];
token[m++]=ch;
if(temp2=='+')
{
zhengfu=2;
repeat=1;
}
else if(temp2=='-')
{
zhengfu=1;
repeat=1;
}
syn=24;break;
case'/': syn=16; token[0]=ch;break;
case';': syn=26; token[0]=ch;break;
case'(':
temp2=prog[p];
token[m++]=ch;
if(temp2=='+')
{
zhengfu=2;
repeat=1;
}
else if(temp2=='-')
{
zhengfu=1;
repeat=1;
}
break;
syn=27; token[0]=ch;break;
case')': syn=28; token[0]=ch;break;
case'#': syn=0; token[0]=ch;break;
default:syn=-1;
}
}
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標籤：基礎類