Write A Program To Implement Stop & Wait ARQ Method .

#include<stdio.h>
#include<conio.h>
#include<time.h>

void main()
{
int dl,i,n=0,n1,p;
char str[25],str1[25],da[25];
clrscr();
printf("\n Enter str : ");
scanf("%s",&str);
dl=strlen(str);
printf("\n");
for(i=0;i<dl;i++)
{
sleep(1);
PVR:
printf("\n    S = %d    |    FRAME %d     |",n);
printf("\n |-----------------|" );
str1[i]=str[i];
str1[i+1]='\0';
scanf("%d",&n1);
if((n==0 && n1==1)||(n==1 && n1==0))
{
if(str1[i]==str[i])
printf("    |    ACK %d     |    R %d ");
if(i>=1)
printf("\n    s = %d     |<---------------|");
else
printf("\n    s = %d     |<---------------|");
}
else if((n==0 && n1==0 ) || (n==1 && n1==1))
{
printf("\nFRAME LOST....!");
goto PVR;
}
if(n==0)
n=1;
else
n=0;
if(n1==1)
n1=0;
else
n1=1;
printf("\n\n");
}
getch();
}