macro processor in c

macro.c

#include<stdio.h>
#include<conio.h>
#include<string.h>
int number=0;
struct table
{
       char data[100];
       char val[20];
       }t[10];
int main()
{
FILE *fp,*fp1;
fp=fopen("input.txt","r");
fp1=fopen("output.txt","w");
int flag=0,i;
char s[100],ch,s1[100],s2[100],s3[100],line[100];
char *temp;
if(fp<0)
printf("\nFile doesnot exists\n");
else
{
while(!feof(fp))
{
 fgets(line , sizeof(line),fp);
 strcpy(s3,line);
 temp=strtok(line," ;");
 if(strcmp(temp,"#define")==0)
 {
                             sscanf(s3,"%s %s %s",s,s1,s2);
                           strcpy(t[number].data,s1);//s1 will have EQ
                           strcpy(t[number].val,s2);//s2 will have ==
                           number+=1;//storing it in a structure!
                           printf("%s\n",s3);
 }
 else
 {
     while(temp!=NULL)
     {
                   for(i=0;i<number;i++)
                   {
                                        if(strcmp(t[i].data,temp)==0) // to compare whether the word is equal to the words in the structure 
                                        {
                                                                     flag=1; //settin flag=1 to print the val given for this word
                                                                     break;
                                        }
                    
                                        }  
                       if(flag!=1)
                      {
                          printf("%s ",temp);//if flag!=1 then it will chuma print the word
                          }
                          else
                          {
                              printf("%s ",t[i].val);//else it will print its respective value
                              flag=0;
                                                  }
 temp= strtok(NULL," ;");                 //this is used to separate the string according to space or ; 
     }
 printf("\n");
 } 
}
}

getch();
return 0;
}