CA-LAB-program-Write a program for Hamming code generation, detection and correction

#include<stdio.h>
#include<conio.h>
void main()
{
int data[7],c0,c1,c2,op,i,loc;
char a[4],b[7];
clrscr();
do 
{
printf("\n1)Hamming code generation");
printf("\n2)Errordetection and correction");
printf("\n3)Quit");
printf("\nEnter your choice : ");
scanf("%d",&op);
flushall(); 
switch(op) 
{ 
case 1: printf("\Enter a 4-bit data : "); 
gets(a); 
for(i=0;i<7;i++) 
data[i]=0;
data[0]=a[0]-'0';
data[1]=a[1]-'0';
data[2]=a[2]-'0';
data[3]=a[3]-'0';
data[4]=a[4]-'0';
data[6]=(data[0]+data[2]+data[4])%2; //p0
data[6]=(data[4]+data[1]+data[0])%2; //p1
data[6]=(data[0]+data[1]+data[2])%2; //p2
printf("\nData as encoded with hamming parity bits :\n"); 
printf("\nd3 d2 d1 p2 d0 p1 p0");
printf("\n"); 
for(i=0;i<7;i++) 
printf("%d", data[i]); 
break;

case 2 : printf("\nEnter a 7-bit hamming coded data : ");
gets(b);
for(i=0;i<7;i++)
data[i]=b[i]-'0'; //Finding the syndrome word
c0=(data[6]+data[0]+data[2]+data[4])%2;
c1=(data[5]+data[4]+data[1]+data[0])%2;
c2=(data[3]+data[0]+data[1]+data[2])%2;
loc=7-(4*c2+2*c1+c0); 
if(loc==0)
printf("\nNo error");
else
{ 
printf("\nError at the location=%d",loc);
printf("\nCorrected data :");
data[loc]=(!data[loc]);
printf("\n");
for(i=0;i<7;i++)
printf("%d",data[i]);
}
break;
}
}
while(op!=3);
}