Counting number of 1s in a number...

A simple and powerful algorithm....for calculating number of set bits....

#include

int CountSetbits(int num )
{
int iCount = 0;
while ( num )
{
num &= (num-1) ;
iCount++;
}

return iCount;

}

int main()
{
int num = 7;
printf("Number of set bits in a number %d = %d\n", num, CountSetbits(num));
}