a single pass assemblers

Single Pass Assembler Program
Question - Implement a single pass assembler.
Program
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
int count[20];
void main()
{
FILE *f1,*f2,*f3,*f4;
int linenumber,locctr,f;
char lbl[10],mne[10],opd[10],ch,mneu1[10],sval[10];
char sadr[10],slbl[10],op1[10],label[10];
void wordcount();
printf("Word count for Input Program:");
wordcount();
printf("\n Output \n");
printf("\n Source Code \t Object code \n\n");
f1=fopen("INPUT.C","r");
f2=fopen("SYMTAB.C","w+");
f4=fopen("INTER.C","w");
fscanf(f1,"%s %s %x\n",lbl,mne,&locctr);
linenumber=2;
while(!feof(f1))
{
if(count[linenumber]==1)
{
fscanf(f1,"%s\n",mne);
fprintf(f4,"%x\t%s",locctr,mne);
}
if(count[linenumber]==2)
{
fscanf(f1,"%s%s\n",mne,opd);
fscanf(f4,"%X \t %s \t %s \n",locctr,mne,opd);
printf("%s\t%s\t",mne,opd);
f3=fopen("OPCODE.C","r");
while(!feof(f3))
{
fscanf(f3,"%s %s \n",mneu1,op1);
if(strcmp(mne,mneu1)==0)
printf("%s\t",op1);
}
fclose(f3);
f=0;
rewind(f2);
while(!feof(f2))
{
fscanf(f2,"%s %s %s \n",sadr,slbl,sval);
if(strcmp(opd,slbl)==0)
{
printf("%s\n\n",sadr);
f=1;
}
}
if(f==0)
printf("0000\n");
}
if(count[linenumber]==3)
{
fscanf(f1,"%s %s %s \n",lbl,mne,opd);
fprintf(f4,"%X \t %s \t %s \t %s \n",locctr,lbl,mne,opd);
fprintf(f2,"%X \t %s \t %s \n", locctr, lbl,opd);
if((strcmp(mne,"RESW")==0) || (strcmp(mne,"RESB")==0))
printf("%s \t %s \t 00 \t 000 %s \n\n",lbl,mne,opd);
else
printf("%s \t %s \t 00 \t 000 %s \n\n",lbl,mne,opd);
}
linenumber+=1;
if(strcmp(mne,"WORD")==0)
locctr+=3;
else if(strcmp(mne,"BYTE")==0)
locctr+=strlen(opd);
else if(strcmp(mne,"RESW)==0)
locctr+=3 * (atoi(opd));
else if(strcmp(mne,"RESB")==0)
locctr+=atoi(opd);
else
locctr+=3;
}
fclose(f1);
fclose(f2);
fclose(f4);
getch();
}
void wordcount()
{
FILE *f3;
char c;
int word=0,i=1;
printf("\n Word Count");
f3=fopen("INPUT.C","r");
c=fgetc(f3);
while(c!=EOF)
{
if(c==' ')
word+=1;
if(c=='\n')
{
word+=1;
count[i]=word;
printf("\n No.of words in %d:%d",r,word);
i+=1;
word=0;
}
c=fgetc(f3);
}
fclose(f3);
}
INPUT.c
WC START 1000
FIRST WORD 5
SECOND WORD 6
THIRD RESW 1
LDA FIRST
ADD SECOND
STA THIRD
END