Hamming Distance... Help Please

[nishant3316]

hi,

I recently wrote this code to calculate the hamming distance between any two binary numbers... The program accepts the numbers in decimals, performs a bitwise XOR operation and returns the HD...

However, it returns the Hamming distance in decimal... that is if after XOR it gets something like 0010... the hamming distance is 1 but the function returns 2 (the decimal conversion of 0010). how do i get it to return the number of 1s instead of the decimal conversion? The code i wrote is given below -

/*This program lets you enter any two decimal integer values... converts them to binary, performs an XOR operation on the binaries, and returns a decimal value for the binary obtained after XOR*/

#include<stdio.h>
#include<stdlib.h>
long int hammingdistance(long int,long int);
main()
{
	long int dec1, dec2,x;
	printf("\nEnter decimal 1\n");
	scanf("%d",&dec1);
	printf("Enter decimal 2\n");
	scanf("%d",&dec2);
	x = hammingdistance(dec1,dec2);
	printf("hamming distance = %d", x);
}
/*this function calculates bitwise hamming distance for the given integers*/
long int hammingdistance(long int x, long int y)
{
	long int dist, hdist;
	hdist = x^y;
	
	return (hdist);
}

[ArkM]

1. Hamming distance for binaries:
http://en.wikipedia.org/wiki/Hamming_distance
2. Use CODE tag for snippets: [code=c] your sources

[/code]

[nishant3316]

Thanks...

Will keep the code tags in mind from next time on...

Cheers

[nishant3316]

hi,

can anyone tell me what exactly this line of the code does?

val &= val - 1;

this the code from which the line's been taken.... it calculates hamming distance...

unsigned hamdist(unsigned x, unsigned y)
{
  unsigned dist = 0, val = x ^ y;
 
  while(val)
  {
    ++dist; 
    val &= val - 1;
  }
 
  return dist;
}

[Aia]

hi,

can anyone tell me what exactly this line of the code does?

val &= val - 1;

That's the same than: val = val & val - 1; Search for bitwise AND assignment, if you want to know more.

[SHIVANGII]

NICE WORK BY NISHant 3316......I WS DOING DIS IN BINARY WHICH WS MAKING IT VERY LONG CODE AND CONSUMINT LOTS OF TYM WHEN I INPUT NUM .YOUR CODE HELPED....THANKS
DIS IS WORKING:

// CALCULATE HAMMING DISTANCE BETWEEN ANY FIXED NO. OF BINARY NUMBERS(here 4) of any no. of bits in certain order

#include<stdio.h>
#include<stdlib.h>

void main()
{   long int d[4],i,j,x,n,dist,hdist;
 clrscr();
// printf("enter the no. of numbers b/w which u want to find HDin order:\n");
// scanf("%d",&n);
 for(i=0;i<4;i++)
 {
   printf("\ndecimal %d :",i+1);
   scanf("%d",&d[i]);
 }
    for(i=0;i<3;i++)
 {
    for(j=i+1;j<=3;j++)
    {
    hdist = d[i]^d[j];
       printf("%d\n",hdist);
    }
  }
  getch();
}
/*************output**********

decimal 1 :7

decimal 2 :12

decimal 3 :3

decimal 4 :8
11
4
15
15
4
11                */
BUT THIS CREATING SOME PROBLEM WHY?????problem is inspite of putting limit(n) of entering d[i],continusly taking digits i.e crossing the n value or u cAn say tangled in loop.why??
#include<stdio.h>
#include<stdlib.h>

void main()
{   long int d[10],i,j,x,n,dist,hdist;
 clrscr();
 printf("enter the no. of numbers b/w which u want to find HDin order:\n");
 scanf("%d",&n);
 for(i=0;i<n;i++)
 {
   printf("\ndecimal %d :",i+1);
   scanf("%d",&d[i]);
 }
    for(i=0;i<n-1;i++)
 {
    for(j=i+1;j<=n-1;j++)
    {
    hdist = d[i]^d[j];
       printf("%d\n",hdist);
    }
  }
  getch();
}