Question { 13575 }

What is the most efficient way to count the number of bits
which are set in a value?

Answer

main()
{
int n,count=0;
printf("enter a number");
scanf("%d",&n);//enterd no.is 5
while(n>0)
{
count++;
n=n&n-1;//binary of n is 101
// binary of n-1 is 100
//n&n-1 is (i.e 101
&100 =100 )

}
printf("%d",count);
getch();
} output is 2(i.e 2 ones in 101)

Question { Microsoft, 26689 }

write a program to find out number of on bits in a number?

Answer

main()
{
int n,counter;
printf("enter a number");
scanf("%d",&n);// let n=5
while(n>0)
{
counter++;
n=n&(n-1);
}
printf("%d",counter);
getch();
}

Question { Adobe, 7389 }

what is the use of pointers

Answer

by using pointers
1)we can pass the function arguments to another function
2)it holds the address of another function
3)it acts as a call back function